I am devastated

My fiance just broke it off with me. We have a 5 month old. I can say most of it is my fault and it's years that we should have broken things off. I feel so bad because I hurt him and our family is broken. I have nowhere to go so I'm stuck there. I don't know what my options are..I'm worried that he is going to try to get full custody of my son if I move let's say back with my mom because he has more money. I didn't save because I was helping pay for half the rent and other bills. Section 8 waitlist are full and I don't know what to do.