Need Advice

For the passed few months I've just been really depressed because I lost my virginity to this boy and he wasn't even my boyfriend but I guess I trusted him and I felt like I really loved him and later to find out in August that he actually had a girlfriend which is why he never made me his girlfriend as well as he was having sex with another girl .I was heartbroken I really love him and then I stopped talking to him for about a month then in late September early October I started talking to him again (stupid me) then I basically fell in love with him again . Then in mid October he got a new girlfriend (again someone over me) and of course I was upset then I was just stupid and I had sex with him Nov 1st and 2nd and those were my main fertile days and I'm not on birth control or anything and he "ejaculated" in me about 4 times and now my period is super late and I told him that there is a possibility that I could be pregnant and he has a great basketball career so he was like he wants me to get an abortion but I don't want an abortion o disagree with them completely and now we've just been arguing and I've became depressed because I feel useless etc. And I feel not good enough . and despite his times I really love him but I don't think he loves me back . he says he does love me etc but why would you treat someone you love like that ? I just really need advice on what to do.