relationship

I've been with my boyfriend over a year we lost our beautiful little boy in January at 23 weeks of pregnancy and since then I have found out he was talking to 14 girls behind my back sending them dick pics and asking them out on dates he says nothing has physically happened and I understand people grieve in different ways but he chooses to ignore me drink and call me names like a slag and a bad mum so I told him I need some space I've tried talking to him he never listens he just ignores me but I want to stay with him because I'm thinking about our son but I'm really doubting if it's worth it and I was wondering if sanyone had any advice. He keeps telling me he is gonna change but now he says he means it.