Forced to be in relationship...

I'm 14 weeks pregnant and I just can't take my boyfriend of over a year anymore. He's so abusive emotionally and mentally and he's so controlling and I just can't take it.... I broke up with him earlier today and he told his mom and his mom, whom I get along with better than my own mom, told him to tell me that he's gonna file for custody to take my baby away from me! Like what the fuck!? He said the only reason she said that was so I can stay. So basically I'm forced to be in this relationship. If I leave, I will most likely lose my baby! What do I do?! My life is hell right now!!