He hasnt hooked up with anyone though. He just wanted to hang out with his friends all summer... thats why I am confused. He hasnt hooked up with anyone, it been me on the end of the phone every night...
With your consent, he has downgraded your relationship to "casual" where he still gets the benefits of being in a relationship without any expectations on him at all, and he doesn't have to go through the pain of a REAL (read: no-contact) breakup. How ideal for him. This is exactly what he wanted, isn't it?
This can go on as long as you allow it, but it's not making you happy. You can either prolong it until he finally moves on, or you can move on yourself and tell him that if he's not in this relationship anymore then you need to sever contact so you can heal.