My gf broke up with me and wont let me try to fix it and is dating her ex bf?

ok well my gf name is jess and her dad is a truck driver and we have a 7 month old son she went with her dad for a week and all the sudden she broke up with me and said she was dating her ex bf mike again and that she loves him and she doesnt love me anymore and that shes never coming home and wont bring my son to me. she said im to controlling and every time i dont get what i want i get pissed wich isnt true one time i asked her not to stay with her dad for a night because i wanted to spend time with her thats what she was referring to. and idk what to do. i've tried talking to her on txt and she doesnt want to come home right now we a re kinda sorta friends we were together for like 1y 7m and sppearently she has been dating mike for like 2 months or so and she cheated on me when we first started dating with him on and off for 2 months because she was dating him right before me. idk what to do i love her so much and miss her alot i really want to work things out but she wont give me a chance she just keeps saysing she needs to listen to her heart. and suggestions?