How to get out of a domestic relationship please help me!?

Hi im 18 have a two year old daughter and im married almost one year but have been with him for four years ever since is was 14. okay im currently living in mexico with him and things have been out of hand he hits me like a man says horrible things to me like im fat ugly etc.. never hits me in my face but all over my body constanly not just one hit its several today he kicked me in my butt that it hurts so bad and he punched me in my back , legs cause i turned away so he wouldnt hit my stomach! he laughs at me throws stuff && spits in my face and he does all this infront of our babygirl! im so tired of this i just want to leave him but my situation is that he is going through immigration to fix his status he is appllying to get his visa and I want to leave him forever i dont want to be him no longer but what keeps me here is our baby I feel like its my fault she isnt going to have a dad cause he wont be able to come back to u.s cause i will no longer help out in the immigration process. i dont want and i dont feel ike he deserves anything from me ! he never apolizes for anything pls help me i dont talk to my family about it they think we are a happy couple! but i cant longer act i want out but i feel so guilty for my child im too young to feel like this pls ! give me advice. thank you..