I'm not going to pay for 50% of my boyfriend's mortgage
Seriously? Can you explain to me why you don't want to help him? Are you planning on leaving?
Yes I will "bail out" on him after he gave me all the money he had.
This seems like something you maybe have not thought all the way through? It's wrong to take money from your significant other and then just leave.
You don't know shit about me, if I want to abandon him after he put everything aside for me, I can. I don't owe him anything and I'm going to "bail out" on him.
Well hopefully he doesn't give you any more money and is able to see through you, because most people would say that you're sounding very crass and cruel right now. You should stick with your supportive boyfriend, because you never know if you'll be able to find another.