Single mom need advise!!!!!!?

I have been separated for more than 1 year with my son's father. my son is 3years old. His father is very disrespectful and has made my life a living hell. manipulating me with threats that if I ever have a boyfriend he will kill me and him or even he will himsefl commit suicide. The reason why I left him was because he was very abusive and is an alchoholic he is 30 years old and is currently in disability due to back problems. I am 24 work full time and attend college part time. I live away from my family the closest relatives are 2 hours away and my parents live out of the country. I have not been able to live a peaceful life since he doesnt pay me child support or helps with my son only when I BEG him because child care is very expensive I sometimes pay 500 per month in childcare and he is sitting at his house doing nothing. so I felt like I needed to be around him as "friends" so that he can take care of my son however He is constatly stalking me and questioning my every move he will never keep my son overnight or on a weekend becuase he says I would go out to be a hoe..... when he is upset he tells my son to call me names and treats me very poorly I finally got tired of it and after being yelled at by my friends and family to report his threats I did.. so he hasnt contacted me however im struggling to pay child care school expenses rent car food and other expenses. my mom is insisting to send my son with her for a couple months or 1 year so that I can save up enough money and relocate back with my relatives 2 hrs away far from my son's dad. What SHOULD I DO. I feel like i will be abandoning my son if I send him out of the country and if I keep him with me I still abandon him becuase I rearly see him since i am at work and he is at day care or with a sitter. HELP please