Most Helpful Guy
He has a similar problem to what I had. He is realizing that he isn't going to be very young forever. He wants to have fun while he still can but he dosnt want to cheat on you so he cut things off thinking either its for the best or he will come back to you.
I know it sounds bad but the best way to keep a long distance relationship like this going (In my experience) is to keep it an open one.
Most Helpful Girl
I always say that if you both really love eachother it will find a way. Many people rekindle flames many years or even months later. I don't know how old you are. But considering the (18 to 24) age range, Don't fret. I remember this stage of worry all too well. Let time take its course.
This age is crucial to adults "finding themselves". You learn a lot about yourself that you may be blinded to when in a relationship. Moving on is your choice. Time usually matures people anyway, why not explore. Don't be afraid to ask for clarity from him you're afraid of his or your choice in exploring (try ask in a non "clingy" way). Good luck!