Should he be with me or her?

Me and this guy dated for 4 months. We were completely infatuated, maybe in love. When things started to not feel right we slowly broke up. He started dating this new girl. He even mentioned her when we were dating and said she is not attractive to him. He can see other people, he has kissed another girl, we have almost kissed. She will let him do anything and he loves the freedom. Who wouldnt if they're with a guy out of their league? Now we are super good friends and things feel right again. He talks to me when she goes to bed and falls asleep on the phone with me. Our connection is still there but i think he feels obligated to her and feels like he's being "smart" by not making it about the physical. But they dont even go out and have fun! He cares about both of us. Should he be with me or her?