ex boyfriend problem

Leslie
Well a guy broke up with me like 6 months ago and he even had like 2 girlfriends in that period of time but we never stop talking he always says he love me and how he is gonna be with me when the time is right I don't believe any of this shit I know him enough to know is just bullshit but every time we are together we act like a couple (yes even if he had a girlfriend in that moment) like kiss all the time, hold hands, have sex and he usually is really sweet with me I think I still have feelings for him and I don't want this to stop but or relationship it's just awful When we try a real relationship it just doesn't work we fight all the time and not a normal fight a really loud he usually hurts me cheating with other girl or making me feel completely useless and a coupe of times we almost hit each other, my friends hates him because they think he is to aggressive and he acts as if i were his property 
I just don't get it why when we are not together we have a awesome relationship but when we actually are boyfriend and girlfriend all go to shit 
I forgot something I don't know but it's a possibility I might be pregnant of him