I went through relatively similar things. Though I had a series of low points before eventually hitting "rock bottom" during the end of University.
I oscillated between "ok" and suicidal as a teenager, due to a number of factors interrupting my pathological hatred of myself and the cross-dressing/dysphoria. The military and having a kid interrupted things for a few years, but after the relationship fell apart I started sinking down into that Jonah like pit of chaos under tumultuous waters.
I was anti-social, manic depressive, anxiety ridden, paranoid, hallucinating at times, and suicidal. I started drinking excessively whenever I'd start having thoughts and desperate feelings to cross-dress and be effeminate. I would consume online stories about people going through transition and then hate myself for wishing it was me, and then drink myself into a stupor and project a happy facade online to friends.
I gained 70 pounds and hit 210 and lived in practical filth. This all continued after I moved back in with family in Georgia. There I got heavy into listening to Dr. Jordan Peterson and decided to do his self-authoring thing. I started critically analyzing my past and all the strongest memories I had. I realized that every single powerful memory had the issue of gender/body dysphoria sitting at its' crux from age 5/6 and onward. I realized as he talked about Big 5 personality traits and statistical norms on how men/women fall on these various psychological scales that in no way did I ever as a youth and even into adulthood ever fall under typical male patterns.
I realized that while there were proximal reasons exacerbating my depression and anxiety, the existential hatred of myself was the ultimate factor. I realized that the happiest point that I had was in high-school when I was emo and basically presenting female or trying to. In doing the self-authoring, I realized that if I didn't try at least some aspects of transitioning; that I would end up old, fat, disgusting, lonely, closeted social-outcast paralyzed by hatred of the Self and fear of reality.
After finishing the self-authoring exercises I realized that simple depression/anxiety medication wouldn't rid me of the fundamental problem, only HRT and transition would do that. I was spending at least 100+ dollars of alcohol a week at that point and smoking and vaping, slowly killing myself.
Once I realized that, everything sort of clicked. I quit drinking and smoking completely cold turkey and coming to terms with the trans thing caused a series of lifestyle changes and behavioral changes that I'd never before been able to accomplish.
I 180'd the shut-in nature and everything else so fast it shocked people. Something mentally changed as well, and something perceptible as well; because I don't feel anxiety anymore in social situations and people don't treat me like a pariah anymore.