College life too much for high school girl?

[Mari]

I have liked this boy on and off for two years. I am a junior in high school and he is a freshmen in college. The past summer break we would hook up every night. It was easy because he is my neighbor. We decided not to officially "go out and be girlfriend and boyfriend" because he is leaving for college soon and it would be hard if we had to break up. Seriously it was so hard just to say goodbye. He is going to college about 45mins. away but hasn't come home in about a month and half. We text almost everyday he always is studying or just out partying on fridays. I know we are not going out but i feel like he is going to meet someone new and he wont tell me. But he told me he doesn't was a girlfriend in college. Is he going to hook up with other girls at parties? I have no clue what college life is like. He is very shy, does not hook up with girls and we both really like each other. When i text him he doesn't even say goodbye anymore like he used to, he just stops texting me. I don't know what to think help plz! Should i ask him if there is other girls when he comes back or before? What should i say?