I think Chris was so pornsick he couldn't get it up for his wife anymore and she agonized over it, legitimately. I'm sure she has and was raised in traditional Christian conservative values. Chris was also. Not being able to have sex now that you can, all the time, whenever you want with just one man? This early into marriage? She probably wondered if she was ugly, or Chris isn't telling her something—haha, which was true—and she worried for their marriage, love and family. I think she kept asking, as any spouse should, and it became harder and harder for Chris to hide the real reason, whether by deflecting the issue and seeing therapists to pacify her and maybe clean up, or by gaslighting her, or spending a lot of time working. She'd sense that he's getting "relief" somehow, and finds out, horrified, what gets him off while she is neglected.
Chris probably trooned out because a divorce was inevitable, in which all his degeneracy would be documented in court. By coming out as trans (and I wonder if coming out as just gay would have had the same effect), he gets ahead of a court record saying his wife is divorcing him because his dick doesn't work anymore, and it doesn't work anymore because it only works when he looks at any of a long list of fetishes. By coming out as a tranny he can shelter all that degenerate fetish cluster beneath his newfound troon identity. It was either be outed as a pornsick sex weirdo in a divorce, a limpdick failure of a man who put cooming above his wife and son, or come out as a pornsick sex weirdo in a dress, and be celebrated for it and vehemently defended by zealots for no other reason.
If his wife files or speaks publicly about him she'll be railed against as a transphobic bigot, that "just because Kris is trana doesn't mean you can accuse her of sexual deviancy". lol
Anyway I don't think it's mental illness at all in Chris's case. I think he thought he could dodge his shame and transform it into pride by means of trannification. His past didn't go away during that tidal wave of support, and it was waiting for him when people lost interest and rallied behind some other troon of the month. Confronting his addiction and seeking help was unthinkable, but as time goes by and he ages, alone, I think he must see that it was the only real way out. If not, another year ticks by for him to reconsider.