When do you call it quits?!?!?!

My husband and I (which thankfully we aren't really married i just say we are by common law bc we have been together for almost 14 years) I should of known from the very start that him and I wouldn't make the best couple.... Long story short he puts me down so badly, especially after I just had his baby 18 months ago... He constantly calls me "fat ass" yeah, i gained weight bc i had a baby!!!!!! Of course that happens... yes, I use to be super skinny, but i didn't lose all the weight yet... He threatens me in front of people like we were in Walmart the other day and he couldn't find me, meanwhile i was literally a foot behind him, and his response was "i should beat the fuck out of you"..... who says that to the mother of their child????? He kicked me out of "his so called own car" meanwhile the only reasons he got that car is because he claimed head of household and our daughter... I had to walk almost 3 miles home bc i didnt have any money on me, and when I got home he had the nerve to sit there and call me a "dumb bitch"!!!!! I cant with him, im sooo unhappy and sad i hardly smile anymore and I get sick to my stomach everytime he has to say little comments here and there... I need the courage to get up and leave for good...