closure help.

trying to come to terms with my 5 year relationship being over... I broke up with him in march due to an anxiety problem I wanted to figure out without hurting him in the process... my therapist agreed that it was the right thing to do. everything has been fine after the break up, he understood, and then we tried talking again, and we were talking for a few weeks.. but he's led me on for the past 3 weeks and over night just stopped wanting anything to do with me. now he's seeing a rebound girl and it really hurts. I'm accepting it's over and that I can't get back together with him, if ever given the chance, because now I've seen this nasty side of him. i couldn't date him again as much as I love him. I just.... don't know how to move forward I guess? I'm stuck still. it hurts, and idk how to leave a life I've known for so long. how did you guys help the pain? I'm tired of crying.... my friends don't want to hear it anymore.... I only have his mom to talk to still (who is just as mad at him for doing this) I just.... I need help girls. I never got my closure.

please help...