hes sweet and then hes distant up and down over and over again


im confused on what he wants but he tells me he loves me then the next minute he says hes done?

ive been with my boyfriend for one year and 3 months and we are expecting a babygirl in late November, but for the past month after we moved into our new apartment, we dont have sex anymore and im a healthy looking prego all belly and he doesnt talk to me he puts me down calls me names has anger problems but doesnt physically hit me its crazy cause we have a great relationship and always have and i understand that in relationships we all have arguements, but the sad thing to say about this is he started doing meth he does it about 3 times a week and on our phone he watches porn when i fall asleep stays up all through the night and gets ready for work and then comes home when he gets off work and ignores me doesnt talk to me, we dont ever go out like we use to like out to eat or movies just little fun dates like we use too, it makes me really sad and when he is high on the meth he moves fast away from me when i touch him or when i just try laying next to him and cuddle, this is the drug story part of it, then when he doesnt do the meth after a couple days he still doesnt talk to me then out of nowhere he bursts out in anger and (im 8 months pregnant) and he starts talking bad to me yelling at me in my face blaming everything on me and i tell him i havent done nothing wrong to you why are you being like this? and it makes him even more mad its sad i been dealing with this for a whole month and i love him so much i do as much as i can for him i cook for him get stuff that he needs im always nice to him i do alot i care about him but he calls me out on things that he shouldnt be doing because i dont do anything to hurt him or to make him angry, im really sadden about this and he tells me that hes over me and doesnt want me there and he wants to be with another girl he pretty much says hurtful things to me and i start crying, im so confused because theres days when he is loving and nice but there is obviously more bad then good what is going on???