Why are you still saying "she"? "she" couldn't possibly wash "her" cock because "she" wouldn't have one. It's time to start unbrainwashing yourself. You're dating a man child. They're super common. You are not responsible for his self esteem or for building him up. It's his choices and actions that brought him to this point and its only his actions and choices that can help him.

You need to think about how this will affect you. If you're honest about the fact that he's a man and you can no longer abuse yourself by submitting to a relationship with a man, what's going to happen? Is he going to tell everyone and get you blacklisted in your friends group? Try to get you fired for being a 'bigot'? While I'm the type to generally say what I think and roll the dice, there are genuine consequence for you to consider here. He also may be a bit unstable. Do you live nearby? Does he know where? How easily can you cut off communication?

I think your best option is to

A) You need to be really clear in your own mind that you're not looking for behavior change, because he will try to negotiate his way back into a relationship with you. If you would stay with him if he behaved differently then there's a different discussion to be had first. But if you just don't want to be in this relationship any more, then honestly the fewer details the better. This is not what you want, the end. "No" is a complete sentence.

B) Reconnect with the support system you cut off. Start today.

C) Pick a good time, when you will be apart for a while, and break up right before it.

D) Be clear but give few details. You've realized you two are not good partners and you don't want to be in this relationship any longer. It's not any one specific thing, and you're not asking him to change. You would like to stay friends (if you would) but you want to take a few months apart without contact first so you can both heal and move on.

E) Just in case it comes up, threatening to kill himself if you do or don't do something is an abusive tactic and your response should be "I'm sorry you feel that way, I'll alert the appropriate services" and walking out of the house while calling the emergency line. A man who's desperate enough to harm himself is desperate enough to harm you too. You didn't mention anything like this, but i recognize the pattern.

F) do not contact or allow contact for a few months. That will just give him hope that you can rekindle something as you have before, at a time when you are both adjusting.

A relationship must be a PARTNERSHIP. Two horses pulling one cart. If one of you is doing all the pulling that's not a relationship, you're the parent to a 30 year old baby.