LongWayHome,
Actually, what you describe is not so very different than the story of my marriage before my now-ex's disclosure. Non-communication, periodic depressions, and the constant silent accusation that there was something wrong with me and all his unhappiness was my fault. Two years before his disclosure, in fact, we had talked about divorcing, but I walked it back--or I thought that was the agreement. When I asked if we could try to fix things, my ex said, "if we can make this marriage work I'm all in," but two years later, when out of the blue he came out to me as trans-identified, complete with plans to have his testicles removed and start taking cross-sex hormones and transition, he said he thought that after what we'd said about divorce he had considered the marriage over and therefore free to re-imagine himself. News to me, because I'd thought we were trying to see if we could make it work. He spent that two years between saying "if we can make this marriage work I'm all in" exploring a new identity, which included telling it all to another person, an ex student of ours, while not only saying nothing to me, but keeping it all secret from me. I heard about it only when he dropped his trans bomb.
During that two years his behavior was to me inexplicably and increasingly hostile and bizarre, and like you, I had no context in which I could understand it. I spent a lot of time in that two years between walking back the divorce and his declaration wondering why the hell he was acting the way he was.
When he did tell me,I at first said "I don't want to be the wife of a transwoman and have my entire life revolve around transness, so I want to divorce" and then was suckered into first "comforting him" and then an ill-advised and ultimately traumatic year and a half of trying to be the "supportive wife." At first he was deliriously happy with me, but I soon discovered that any doubts or discomfort on my part were unacceptable to him. He not only had absolutely no empathy for me or appreciation of what I was attempting, he didn't believe I was due any, either. I spent that eighteen months largely caught between my intuition that I needed to get out of the marriage and trying to support my husband, and living in his closet, which left me isolated and vulnerable to his manipulations. I am so grateful that my own intuition was not extinguished; in fact, it grew more insistent over time, to the point I was having dreams in which I was in a building looking for an exit and hearing a voice say "You have to get out."
Recovery is hard, difficult, exhausting work, and we need to care for ourselves. The effort, though, is so worth it. I now regularly find myself realizing that I'm content and happy, and then thinking how new and surprising this feeling is. That the feeling is such an unusual one reminds me just how unhappy and discontent I had gotten used to feeling.