Hi there, I've been lurking on here for a while, reading other people's stories for consolation, and trying to make sense of mine. I've been through so much with my spouse. I've known him since I was little. We've been married almost 14 years and have 2 kids together. 
Years ago, after I had come back from out of town, I found a women's sweater dress on our bathroom floor. I called him immediately in rage, thinking he had been cheating on me. That's when he admitted that he sometimes liked to dress in women's clothes, but that it was no big deal. I was young, naïve, and stupid, and though it bugged me, I tried to dismiss it as a kink. Shortly after that, I got pregnant with my daughter, we got married, and started real adult-life together. 
During my daughter's babyhood and toddler years, he struggled with major mental health issues. It was a very painful period of time for me as a young mother, with a partner that did not seem to like his life or our life together. Then I would find things in his bathroom -- fake boobs/make up etc. Things I could not explain, but was in too much mental anguish of my own to really address in a truthful way.
Shortly after the birth of my son, my spouse had his first psychotic break. This pattern repeated eventually leading to a diagnosis of bi-polar disorder. During one of these breaks, he admitted to me that he sometimes dressed up femme and posted pictures of himself to get feedback on (what I've come to learn recently during my own research), how well he "passed". Again, as a mother of a baby, dealing with a husband on disability due to mental health issues, tackling the full extent of this was more than I could bear. 
Fast forward to years later, we buy a house, continue raising our kids. Have a decent marriage for a while, but there is always this nagging feeling in my gut. Then there are the endless discoveries, "femme" things stashed away in the basement, sometimes left out accidentally. A couple times him suggesting he dress up (which I reluctantly allowed, after a few drinks) He has another manic episode, which leads to a long period of strain in our marriage, eventually leading to a separation.  Too many details about that time to list here, but suffice it to say, it was terrible.
After a few months, we started couple's counseling and decided to try to reconcile our marriage. I knew that there could be no truly moving forward unless we delved into the "elephant in the room" in our marriage, which was his cross-dressing and how deep the issue effected him. So we started exploring it. I started to engage him openly and honestly, attempting to create a safe space where the truth of this could finally be flushed out. I was sincere in my efforts; I desperately wanted my marriage to work, especially for my kids' sake. Unfortunately, what started to be uncovered was a truth that was much bigger than I could bear. A dysmorphia that permeated him very deeply. He would say things like "sometimes I just think of us as a lesbian couple" (ouch), or lament that he couldn't be like one of the girl complimenting another woman on her hair or makeup, that he mostly did not view women sexually, but rather with envy on how he could mimic their fashion or looks. Then there were the physical changes -- he started growing his hair long, losing a significant amount of weight and muscle, talking about wanting a nose job to be more androgynous. Botox, chemical peels, tons of money on moisturizers and products. Oftentimes using my products, and buying the exact same kind (which feels violating). Also violating was when he would steal and dress in my clothes, something I've expressed upset me many times.  It started to feel like I was losing my husband, and I went into a sort of mourning. The worst part was when I tried to talk to him about it, he would get defensive and just overall exhibit a real lack of empathy, which, along with not respecting my boundaries,  I thought was a huge red flag. 
I started researching these issues, and reading stories of the path this could potentially take. He has never labeled himself as trans, or verbally declared a desire to transition, but it just seems like something he is incrementally doing. The more stories I read, of women who stayed and those that left, the more I knew this path was not for me. I'm 40, and did not want to wait another 10-15-20 years for him to realize his full "truth" and our lives be even more deeply intertwined at that point.  I was desperate for answers from him, but I don't even think he's being honest with himself or knows the answers. I used to urge that he seek out a gender therapist, or group, to understand his issues more deeply, but he seems reluctant to align himself with the trans community or accept this as his truth. At this point, I think I know more about trans issues than him (although it's possible he's just being secretive about his involvement and understanding) So during our last counseling session (months ago now), I said out loud what the truth inside had grown to be--he could not give me romantically what I needed in a partner. I had a very chaotic and trauma filled youth I'm in at a point in my life where I need safety, stability, and strength from my partner. He would say things to me "well you seem masculine" as a way to justify our compatibility with his feminine side? The thing is, I'm ready to be a little "weak" or vulnerable and rely on someone. I feel like he misgendered me to fit his narrative and delusional truth he's concocted. 
Since then we have just co-existed in the same house, co-parenting our kids Our only interactions revolve around the kids and the daily goings-on of life. But I'm miserable. I'm so sad, angry. I feel used and cheated out of the best years of my life. I feel like I picked him, missing out on great partners, but knowing my kids resulted from it and grateful for that. I feel like a failure in my marriage, and to my kids. I'm terrified of the future financially, emotionally. What I stand to lose. Him, my house, his family who I've known for over 25 years. Of course none of them have any idea any of this is going on.  I still dream about him, being with him as a man. Then sometimes I'll dream about him in femme, and feel all the sadness associated with that. 
And he's so passive. I think he's hoping one day I'll just wake up and magically be ok with everything, and support him unconditionally through this journey. I tried, I can't, I was losing myself completely to it. He doesn't seem to accept that is not the case. We do not communicate very well anymore, I feel completely shut down, like I've lost the ability to talk to him. I can't bring myself to discuss any path forward, so I just ruminate internally on it all day. 
I just want to feel better. For life to move on. For him to let me go out of a place of love and recognition, that we can't give each other what we need. I want to win the lotto so financially my kids will be unaffected by this. I feel completely stuck and miserable. 
I want to thank everyone here for sharing their stories, they have been a small ray of a light on this very dark journey.