i need your advice please

so me and my boyfriend are about to go to different schools and we've been talking  what's gonna happen after graduating. i asked him if he's still gonna be with me.. i know you're gonna think why i would ask.. well he's left me a couple times before because he wanted to find himself before he gets into a relationship, or because he wants to focus on school or in himself like partying or whatever. which has hurt me really bad because each time we got back together he would basically get my hopes up, then say nvm i have to focus on myself; then leave. he's not a bad guy, he can be really sweet, we're best friends. the only time he's done something bad was when he danced with another girl while we were together. after that, he's been trying his best to make it right, he's really nice etc. ever since then, i lost trust and i've been thinking about it a lot so i guess you could say i've been sad & not the same. so about that, i've been over thinking that he would do something like that again or that i'm not enough.. which is okay in a way because of what he did; i mean you can't expect me to be happy. i'm happy but it just comes back to me sometimes it's normal. i also think about how he might leave me after graduation because of the same reasons before, he wants to focus on himself. i love him so much that i understand he wants to study, he wants to go to school.. we talked about this and he's making it seem like he will never have time to talk to me or hang out with me.. he says "i don't want you to say that you couldn't do something because of me or you couldn't be with me to do something".  he said he needs to grow and that i need to grow and we can't do that if we're together. i told him he's making me feel like i'm extra weight he doesn't need... but he said it's not like that. he says he's with me now and just waiting it out to see what's gonna happen... he told me that after our argument about him dancing with another girl our relationship hasn't been the same, that's it's just a routine now. 
i know our relationship can work while we're in college, but he doesn't have that type of mindset. he thinks he has to spend money and spend every minute of the day with me. we're gonna be on college, i'm gonna be understanding. he's just thinking about it differently.
i don't know what to think or say about it anymore.