From the outside, Christina, a 52-year-old woman from the Southeast, lives a fairly conventional middle-class life. She lives alone in a condo. She socializes with friends regularly. She travels as often as she can.

Once a week, Christina drives to an independent living facility where her longtime husband lives. He was diagnosed with Alzheimer’s disease in June 2016, and his health quickly deteriorated. Unable to continue caring for him on her own, Christina sold the home they’d shared in 2017, moved into her own place and helped her husband settle into the facility.

Her husband’s condition, and the shadow it casts over Christina’s life, is common knowledge in her town. What isn’t, though, is the fact that she’s been in a relationship with another man for over a year and a half. They met on Ashley Madison, a dating website that’s marketed to people who are married or otherwise partnered.

“Only my hairdresser knows,” she says with a laugh.

Christina’s situation isn’t unique. Earlier this year, the internet ignited when Dan Gasby, the husband and business partner of lifestyle guru B. Smith, shared a photo of himself with his new girlfriend. Smith was diagnosed with Alzheimer’s six years ago, and the disease has progressed to the point where she has trouble communicating. She and Gasby are still married; Gasby’s girlfriend shares a home with them. It’s a living arrangement that enrages many of B. Smith’s fans.

But the trio’s situation scratches at a question: How do couples sustain relationships and navigate intimacy when disease or disability strikes?

Christina — who asked to be identified by her first name because of privacy concerns — says her marriage was very happy and she loves her spouse deeply, but now that his disease has progressed, she no longer recognizes the person he’s become. She and her husband didn’t discuss what would happen to their marriage once the Alzheimer’s truly took hold. And according to Alison Graft, a therapist with The Gottman Institute, this isn’t unusual.

“A lot of times, the reason people don’t want to talk about [intimacy once a partner is ill] is because they don’t want to burden the other partner,” she explains.

The healthy partner doesn’t want to guilt their ill significant other about the lack of intimacy, Graft says. This is especially true because, when placed next to the stress of living with illness, feeling randy might seem like a not-so-important problem.

Another reason couples may not discuss next steps is because there was friction in the marriage before they were confronted with serious illness.

“If the relationship already had some of these negative patterns of communication, then the illness or trauma exacerbates the problem,” Graft says. “It can really highlight any cracks that were already there.”

That’s the case with Anderson, 42, who also requested to be identified by her first name for privacy purposes, and her husband. They’ve been together 20 years, married for five, and share an adolescent daughter. But according to Anderson, only a handful of those years have been happy.

“When I fell in love with my husband, I forgot to ask him to love me back,” she says.

Four years ago, Anderson’s husband got so sick he was in the hospital for a month. Now, he deals with chronic pain — and this has affected the couple’s sex life. According to Anderson, the marriage has been sexless since 2015.

“Even before he got sick, I felt like I was constantly initiating intimacy, but he wasn’t receptive,” she says. “When he got sick, I became the enemy.”

Anderson, who lives in the Northeast, joined Ashley Madison four years ago, shortly after her husband became ill. “I just got tired of being lonely and feeling empty,” she says. “I was feeling a little bit lost.”

Initially, Anderson wasn’t necessarily looking for physical intimacy.

“I was just looking for someone who understood my feelings,” she says. “I was looking for someone who was in a similar situation to me.”

She’s had four relationships since 2015, and she’s hoping her current relationship will turn out to be a long-term affair. Anderson still lives with her husband and serves as his caretaker. She hasn’t told him or anyone else about her extramarital relationships. If her husband dies before she does, she says, she doesn’t want to remarry.

Christina, like Anderson, wasn’t initially seeking a sexual relationship outside her marriage. But she says she hit a breaking point about a year after her husband was diagnosed with Alzheimer’s.

“Being a caretaker is rough,” she says. “It’s exhausting mentally, physically and emotionally. I just felt like I needed a conversation with a man who appreciated me. It was just wanting to be appreciated as a woman, and wanting to escape my situation.”

Both women say that it’s this desire — the impulse to reject their role as caregiver — that they feel is most stigmatized. Neither Christina nor Anderson plan to leave their husbands. Christina’s husband has no other family, she says; if she were to leave, there would be no loved one to care for him. Anderson says she stays with her husband because of their daughter.

“I also still have love for him,” she says.

But both women grapple with the demands of caring for a sick spouse. Partners, especially women, who are in good physical health are often expected to step into the caretaker role. That can take a toll, experts say.

“It’s easy to judge, but you have to look at someone’s needs and the situation that they’re in,” says Melvin Lee Phillips, a psychotherapist and author of the forthcoming book “Sex and Love When You Are Sick.” “In partnership, we have emotional needs, and we have sexual and erotic needs. When one of those gets hit, it can cause a domino effect.”

Critics may point to marriage vows, claiming that spouses make a pledge to love and care for one another in sickness and health.

“Some might say that the cheating partner is violating those vows,” says Tammy Nelson, a therapist and author of “When You’re The One Who Cheats.” “But considering how much longer we’re living, and how complicated life can become in those intervening years, I think that there needs to be an amendment to marriage vows. Life is complicated, and so is partnership.”

Both women acknowledge their decision to cheat may raise eyebrows, but they’re quick to point out that their needs are important, too.

“Women are expected to be caretakers, but we’re not allowed to participate in the joyful things,” Anderson says.

Christina echoes that sentiment.

“Unless someone has lived my life, they have no idea what it’s like,” she says. “If I don’t take care of myself, then there’s not going to be anyone to take care of my husband.”

“I’m just doing what I need to do to save myself, too.”

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