@Akamas - This is all too familiar.  I am in a similar situation but my husband has not said the words that he is same sex attracted to me but he skirted around that saying everything but and I do know based on something I saw that he said those words to his therapist and this has been his whole life.  We have been together 23 years.  I am still in the emotional turmoil phase, not knowing what to do, trying to make whatever work for now but I cannot live separate at the moment. What I want you to know is this is NOT your fault at all.  The intimacy, the relationship issues, not wanting to be with him because it's so hard knowing this and accepting this, being unhappy and insecure, this is a normal and too common a feeling us as straight spouses feel.  Nothing is your fault.  I am so proud of you and happy that you made the decision to live separately where you can work through your feelings.  Your feelings are OK and so valid.  You do not have to be okay with this.  I would love to hear how you are doing once you are living apart.  Wishing you all the best in this horrible situation and please reach out here or directly if you want to talk.  I am so sorry you are going through this. 

Blueberry,

    I am the ex of a trans-identified man (aka a "transwoman").  After my ex disclosed, I stayed for three years, trying to wrap my head around him, trans-ness, and the thoughts and feelings his disclosure, words, feelings, and actions raised in me.  What you are saying about the way your ex accused you, and the way you are reacting, rings very familiar to me.  So this is what I from the perspective of 11 years past disclosure, and eight years past moving out and divorcing, want to tell you:

His porn addiction and his "feminine feelings" have nothing to do with you.  They do not have anything to do with your loss of libido from taking antidepressants or from your undergoing perimenopause. 

Nothing you did or failed to do "caused" him to do anything.  He made the choice to view porn and to fall down the porn-fueled rabbit hole. His choices and actions are not, and were never, your fault.  

It took me several years after disclosure and leaving--so at least five years--to realize that a pull to trans porn and trans content in general is not simply one choice among many, but that a man who chooses that path, of trans porn, cross dressing, and forced feminization has a predilection toward it.  It's not just one choice out of many out there.   

Straight men on this site have been known to tell women here who are struggling with their partner's "explanations" that straight men never choose to view gay porn, although a gay in denial or closeted spouse might tell his wife that his choice of gay porn and gay hookups are just "curiousity."  It's a specific choice our partners chose because that is the way they are.  

I repeat: the choices your ex made were not a result of your antidepressant use, your perimenopause, or anything else about you or what you did or did not do.  They were his and his alone.  You are not to blame for them and not responsible for them.  Full stop.
 

"Did anything specific help you make sense of it all and come to terms with it?"

I'm still struggling to make sense of it.  I have to be honest: I'm not really sure that I'll ever recover from the trauma of having my entire reality altered, for over half my adult life.  

In the very beginning, I was charitable towards him -- but bear in mind, I didn''t realize how much lying had gone on and was still going on.  I also didn't realize how much he'd stolen in terms of marital funds.  I didn't realize he'd had two and a half decades to prepare financially for this eventuality, while I was still in shock trying to understand what had really happened.  

Your husband came out as "bisexual" but do you think there's some wiggle room in that explanation?  A person who is bisexual should, in theory, be capable of building a real connection with either sex.  They shouldn't be coming to you saying they need to have a same-sex relationship in order to be fulfilled.  If he requires same sex relationships, the correct term for that is "gay".  My husband couldn't face the reality of his own dishonesty, so he told himself that he was "bisexual" but the truth was, for most of our marriage, he couldn't perform sexually with me at all.  The fact of his being able to have sex with women when he was in his teens and 20's doesn't mean he was "bisexual", it means his hormone levels back then were strong enough that he could overcome his own homosexuality.