Dealing with a break up during pregnancy

Hello, I'm 28 weeks pregnant & I've was with my partner for 3 years. We have had our ups & downs. He has his problems with drugs but was always able to overcome them after wee blips. Although at my 27th week off pregnancy he started using again. I warned him if I caught him doing it again I would leave him and he just went straight back and done it again. I'm so heartbroken I had no choice but to leave. He's off them now but j just can't trust him, we were living together & had all the nursery done and everything bought for our wee daughter coming in November. Now I'm having to move back in with my mother & I'm so drained and hurt. Not only have I lost my partner but I've lost my home and my best friend. I've told him maybe once child is born we can try start dating again once he proves himself but I'm just finding it so hard to deal with having trouble eating and sleeping. Any advice?x