Denise attended medical school with aspirations to become a surgeon, however because her high levels of anxiety prevented her from handling such a profession, she eventually changed her focus of study to psychiatry. She also had a twin brother named Dennis, who was six minutes older than her.
She described him as being brave, yet dangerous; it is likely that because of this behavior, this is the reason he died during the early days of the apocalypse.
Denise ultimately agrees to help, but fails anyways as Holly dies. It is implied that she stabs Holly in the head to prevent reanimation afterwards.
Denise is first seen listening to Rick's speech at the town's gates.
He replies that he had freed the people he has murdered.
It is revealed that Owen knew that she didn't know that Morgan had held him prisoner. He vows that he has done his part and that the world will take his role after his death.
"I asked you to come with me because you're brave like my brother and sometimes you actually make me feel safe..I wanted you here because you're alone. I could have told her I loved her, but I didn't...because I was afraid.
Probably for the first time in your life, and because you're stronger than you think you are, which gives me hope that maybe I can be too. That's what's stupid, not coming out here, not facing my shit, and it makes me sick that you guys aren't even trying because you're strong and you're smart and you're both really good people, and if you don't wake... and face your..." Denise Cloyd is a survivor of the outbreak in AMC's The Walking Dead.
Denise was living in the Alexandria Safe-Zone and remained largely to herself, presumably because of her anxiety, which is why she was mainly not seen when Rick's group first entered Alexandria or at Deanna's party or the community forum when Reg and Pete were killed. After Pete's death, Denise was tasked with taking over the medic duties for the community.
She had initially offered her support to Pete, but he turned her down. Denise is first seen studying in the clinic when Tara and Eugene come in looking for aspirin.
She is later found by Tara sulking on the floor of the clinic in frustration over her lack of medical ability.
When Tara tries to encourage her, she tells Tara that the patient she's currently treating will most likely die.
Denise insists on examining Tara when she complains about a headache.