She was born in Stamford, Connecticut and currently lives with her husband and two children while working as a secretary for a law firm in Fayetteville, North Carolina.
Diaz-Twine seemed like an early target for her lack of physical strength and inability to swim, but her knowledge of the Spanish language and her resourcefulness, which helped their tribe Drake gather much needed resources from local traders at the start of the game, put her in good standing with the majority of her tribe. She eventually formed an alliance with Rupert Boneham, Christa Hastie, Trish Dunn, and "Jonny Fairplay" Dalton. Diaz-Twine was the first person to sit out of a challenge and the first to raid on Morgan's camp as part of the reward, where she not only took their tarp, but sabotaged their shelter. When Drake lost the fourth and fifth immunity challenges, the alliance voted out the minority alliance's Burton Roberts and Michelle Tesauro. When Drake lost the sixth immunity challenge, the originally-targeted Shawn Cohen was saved when Diaz-Twine turned the alliance against Dunn for instigating an attempted blindside of Boneham.
With the Drake and Morgan tribes even at five members each, they were shocked when the six contestants who had been previously voted out came back into the game as a third tribe, in a turn of events called the "Outcast Twist." When the tribe of Outcasts competed against the Drake and Morgan tribes and subsequently won the immunity challenge, two of the Outcasts were allowed to return to the game. At the same time, both Drake and Morgan were forced to vote out a tribe member. In a game-changing move, Diaz-Twine, Boneham, and Hastie, unsure about whether to send home Cohen, the last minority alliance member left, or Dalton, who betrayed them previously together with Dunn, asked them to publicly campaign for their spot. The alliance eventually eliminated Cohen, and received Roberts as a replacement from The Outcasts.
As the tribes merged into Balboa at 5–5, the Drake tribe, with the help of outcast Roberts, was able to sway Morgan outcast Lillian "Lil" Morris to vote with them, controlling the game and subsequently voting out Morgan leaders Andrew Savage and Ryan Opray. However, the game took a major shift when old Drake members Dalton and Roberts aligned themselves with Morris, and recruited the remaining Morgan members Tijuana "Ti" Bradley and Darrah Johnson. This new alliance successfully targeted Boneham and he was blindsided.
At the Final Seven, it seemed that Diaz-Twine and Hastie were doomed by this newly created alliance, but Diaz-Twine swayed Bradley and Johnson by spying on Roberts and Dalton to expose their intentions to eliminate the Morgan girls after getting rid of Diaz-Twine and Hastie. However, when Roberts and Dalton learned of this impending mutiny, they regained the trust of Diaz-Twine and Hastie (with the help of Dalton's infamous "dead grandmother" lie) to successfully blindside Tijuana. Soon after that, they were betrayed once again when Roberts and Dalton switched sides and Hastie was voted out next.
At the Final Five, Johnson was the next target of Roberts and Dalton, but Morris started to have suspicions about her alliance (which would prove true eventually). Roberts made a potentially fatal error by inviting Dalton on his reward trip, leaving the three women, including an angered Morris, together back at camp, sparking a last minute scramble to break the bond between the two guys, eventually voting out Roberts for the second time in the game.
After Diaz-Twine made it to the Final Four, she was no longer a target, with Morris and Johnson targeting each other, each believing that no one could win against her in the Final Two. Diaz-Twine and Dalton decided to side with Morris and vote out Johnson, propelling them into the Final Three. In the Final Three endurance immunity challenge, Morris won and chose to eliminate Dalton, an error that led to Diaz-Twine's ultimate win.
In the end, after having previously stated that no one could ever win against Morris because she was too nice, Diaz-Twine annihilated Morris, winning by a vote of 6–1 to become the Sole Survivor. During her final statements at Tribal Council, Diaz-Twine described her strategy as being the one people would come to if they needed one more vote to oust someone ("anyone, as long as it ain't me"). She gained the votes of Opray, Boneham, Hastie, Roberts, Johnson, and Dalton. Only Bradley voted for Morris.
After declining a spot on Survivor: All-Stars and then being cut at the last minute from Survivor: Micronesia, Diaz-Twine accepted a spot on Survivor: Heroes vs. Villains. She was one of four previous winners chosen; the other three were Tom Westman of Survivor: Palau, Parvati Shallow of Survivor: Micronesia, and James "J.T." Thomas, Jr. of Survivor: Tocantins. At the start, Diaz-Twine was placed on the Villains tribe, and in the first episode, when host Jeff Probst asked who believed they were on the wrong tribe, she was quick to raise her hand. During the first reward challenge, she deliberately tore Hero Jessica "Sugar" Kiper's top off, which, according to Heroes member Cirie Fields, solidified why Diaz-Twine was chosen as a Villain.
In Episode Three, when the Villains faced their first Tribal Council, Diaz-Twine stuck with her strategy from Pearl Islands of "anyone, as long as it ain't me." She, along with the rest of the Villains tribe, unanimously voted out Randy Bailey from Survivor: Gabon. Despite previously appearing to be in a comfortable six-person alliance, by Episode Eight, she found herself on the outs of her tribe alongside Courtney Yates of Survivor: China. Despite the pair being considered the weakest on the tribe, Diaz-Twine convinced Russell Hantz that Benjamin "Coach" Wade was against him, and she and Yates survived elimination at Tribal Council. Yates, however, would be voted off in the subsequent Tribal Council.
After the merge, Diaz-Twine pleaded with the Heroes not to trust Hantz. However, they did not listen, and despite several attempts to oust him, she remained with the Villains after her plans to help the Heroes failed to materialize. She made it to the Final Three, along with Shallow and Hantz. On May 16, 2010, Diaz-Twine received six jury votes from Yates, Heroes tribe members Thomas, Amanda Kimmel, Candice Woodcock, Boneham and Colby Donaldson to Shallow's three and Hantz's zero to win the game. She became the first and, to date, only contestant to have won Survivor twice. With this, she has been known as the self-proclaimed "Queen of Survivor."
Diaz-Twine entered Survivor: Game Changers as one of three former winners. She had an especially big target on her back since she had won twice prior. She was initially assigned to the Mana tribe. After losing the first Immunity Challenge, Mana made an easy vote and decided to unanimously vote Ciera Eastin off for playing too hard, too early.
The day after Eastin's elimination, Diaz-Twine made an alliance with Survivor Cagayan winner Tony Vlachos on the basis that they were both major threats. The duo planned to link up with J.T. Thomas, the other past winner in the game, should they ever meet on the same tribe. She and Vlachos pulled in Aubry Bracco, Caleb Reynolds, and Malcolm Freberg, and thus the alliance of five seemed to control the nine-person Mana tribe. However, on Night Five, Vlachos caught Diaz-Twine talking with "Troyzan" Robertson in the middle of the night. Even though she had not reneged on the alliance, Vlachos misinterpreted the conversation and confronted her. This resulted in her and Vlachos turning against each other—him for seeing her as too major of a threat, and her for not wanting to be controlled by another person. Mana narrowly lost their second challenge and they were set to return to Tribal Council. She gathered her troops; she spoke to those who were on the outs of the alliance of big threats, namely Hali Ford, Jeff Varner, Michaela Bradshaw, and Robertson. She wanted them to vote with her to take out Vlachos. At Tribal Council, Diaz-Twine voted against Bracco in the event that Vlachos played an idol. The rest of the tribe voted in her favor and sent Vlachos packing.
Day Seven brought a tribal split. Diaz-Twine was sent to the Nuku tribe. Fortunately, the former Manas had a 5–1 majority on the new Nuku, with Thomas being the odd man out. Nuku won the third Immunity Challenge, and later the first Reward Challenge, winning coffee, cookies, and pastries. During this time, Thomas was plotting behind Diaz-Twine's back to take her out of the competition.
At the Day 11 Immunity Challenge, Jeff Probst revealed that the two tribes who lost the Immunity Challenge would be sent to one Tribal Council, where they would collectively vote one person out. Nuku had an early lead due to Varner's proficient communication skills, but he ultimately lost the challenge at the table maze stage. Nuku was set to head to Tribal Council with Mana. During the afternoon, Thomas continued plotting against Diaz-Twine, mainly with his new ally Freberg. However, the rest of the tribe planned to vote together. They planned to vote against Sierra Dawn Thomas (no relation to J.T.). At a chaotic Tribal Council, J.T. had told Mana that Sierra was Nuku's target, and hoped to get the Mana tribe to blindside Diaz-Twine. In the end, Nuku continued with their original plan, piling their votes onto Sierra. Unfortunately, Tai Trang played his hidden immunity idol on Sierra, negating the six votes cast against her. Freberg was taken out, much to the chagrin of the Nuku tribe.
Freberg's untimely blindside infuriated Diaz-Twine, who, after Tribal Council, confronted J.T. She planned to get him out for his "dirty deed" should Nuku lose the next Immunity Challenge. At the second Reward Challenge, she helped Nuku win peanut butter and jelly sandwiches by completing the puzzle. After the challenge, she played on the brewing feud between J.T. and Bradshaw. She escalated the tension by consuming the tribe's sugar and putting the blame on Bradshaw. Nuku went on to lose the Immunity Challenge, sending Diaz-Twine to Tribal Council for the fourth time. She seized the opportunity to exact revenge on J.T. At Tribal Council, J.T. and Bradshaw's fight reached a fever pitch. Diaz-Twine took advantage of this to secure Bradshaw's vote. She pulled the wool over Bracco and J.T., and with Varner's vote, J.T. was sent home with an idol in his pocket. After Tribal Council, Diaz-Twine made clear that Bracco was next on her list, since she had failed to gel with the rest of the Manas during her time in the game.
A second tribe switch occurred on Day 14, but although Diaz-Twine remianed on Nuku, she was relegated to the bottom with Varner, as the original Nukus who returned to the tribe held a five-to-two numbers advantage. The Nukus planned to get her out for being a two-time winner. Her fate was sealed when Nuku lost the Immunity Challenge. However, she saw through the Nukus' lie that she was safe over Trang, and she tried to gather votes by telling Ozzy Lusth, Sarah Lacina, and Andrea Boehlke that she would vote with them when the merge hit. Diaz-Twine planned to throw Trang under the bus at Tribal Council. But during Tribal Council, Trang whispered to her, telling her to vote against Lusth. She made a last-ditch attempt to gather votes against either Lusth or Trang (for his perceived duplicity), but this was all for naught. Diaz-Twine left the game in 15th place to an ovation, in a 5–2 vote. However, she emerged as the highest-placing former winner in the season.
In 2013, Diaz-Twine was in the audience of an episode of Dr. Phil to support her friend and fellow Survivor winner, Todd Herzog, who was struggling with alcoholism.