How do i get over her?

ok well i posted a question on here before about me and my ex and our situation and the advice was helpfull but now its gotten even more complicated. so a recap is that i dated my ex for 9 months and we both gave everything up for ecahother but when she went back to her family in cali for a month she cheated on me 4 times. then she came back and i had no idea. i proposed and she said yes and then we moved in together and lived together for 3 months. so while this was going on i introduced her to one of my "friends" and they started talking behind my back and having behind my back...i felt something was going on and i confronted her and she told me everything including the cheating. so she chose to live with him and left me. shes is living with him and ******* him and she doesnt know anything about him and vice versa. they have only known eachother for a week. now to my point. i let her go and did what u guys advized me to do but now to make things more complicated and harder on me we found out that she is pregnant. i dont know if its mine but im pretty sure it is. and she doesnt want to come back to me or be with me and she doesnt want to keep the baby. she wants to abort it. she also said the reason for wanting to be with me is because she wants to see if it will work out with him and if it doesnt she wants me to take her back. i told her i dont want her back and i dont wanna see or hear from her again but i truly do. i wanna forgot it ever happened and i want us to have the baby. idk what to do or how im supposed to feel. i cant stop thinking about her and the baby and the [possibility that theres still hope and i know for a fact he just gonna use her for the and then dump her to the curve and her whole family knows about this.they dont like her anymore. what should i do? please help me....im dying inside and havent been able to reall eat or sleep.