For five months, we've been crazy about each other, planning a future together. He wanted to move and come live with me, pay the mortgage for the house together with me and get married.

Wow.... you just came out of a disfunctional relationship where you've realised that you need to work on yourself and then shortly after you get together with the next guy? And after only 5 months you're already talking about stuff like that? Don't you think that this is a red flag? I mean your bf is 45 years old. He should know better than this.

I have been crying for four days straight and he is cutting me off almost completely. Today I haven't even gotten a good morning text and now he will only send one line of text and then shut off his phone for hours. I don't know what to do except die

Look, you shouldn't immediately become dependent on another guy again. See this as a chance to work through this yourself. Talk to your parents and tell them to find a new place to live. Start looking for buyers for your house. Focus on yourself.