@Aliona,
What kind of "cheating"?
You went out? Hugges? Kissed? Sex?
I'm not an advocate of LD relationships for young people. People are just too energetic, vibrant, at their social and emotional highs, and are prone to be sexually explorational.
Most likely your guy is in the same boat as you.
Agree to date others while you are away from each other. If you are meant to be more than that, time will allow you to come together.
You are not ready to be exclusive to an absent partner. Admit that to him.