babys dad?

ok so im 19 weeks babys dad has hardly been around since day 1 we were not together when i got pregnant btw ...... we last talked jan 15th and had a new gf the nxt day well his gf hates me from probs when we were younger with that being said babys dad called me a "mutant" jan 15 n that hurt so i blocked both his fb acounts n changed my cell number well he has not made any attemps to talk to me from what i hear hes going around telling ppl i basicly raped him witch idk how i can considering i all ways made him go on top.... only person in his family he has told is his dad.... his mom does not no that hes going to be a dad should i try n conctant his mom ? and ask if her son has plans to be part this babys life considering she is a good person or should i just forget him im so confused and stressed