Most Helpful Guy
I have a few comments on this. The first is that I don't really find it surprising. You weren't that deep into the relationship with your boyfriend and maintaining a long distance relationship is very hard especially if you don't have a really solid relationship built before you're separated. It is not at all unusual for relationships to fall apart when one person goes away. Doing things together in person is important to keeping relationships strong and you can't do that when you can't be physically together.
Some people seem to be trying to shame you for cheating, but at your age and with your current relationship being only very short, I don't really think it's anything to be ashamed of that you'd rather be with someone you can be with, particularly if you feel a strong connection. Dating at your age is about finding the person you're most compatible with and can be most happy with. I would not feel guilty about ending a short-term relationship because you think you can do better. I'd feel differently if you'd been together for years or certainly if you were married, but not in your situation.
I don't think there's any way to dump someone that won't hurt them so you have to accept that. I think I'd just tell your boyfriend that you really like him and enjoyed the time you had together, but it's just too hard being apart from him and so you want to date someone that lives near you so you can do things together. (I'd avoid mentioning the new guy unless he asks.) In the long run, it might be better for your boyfriend too because he'll then be free to explore relationships with someone new that he meets there and that he can be together with in person.
Most Helpful Girl
It you’ve been dating for 3 months and he’s away at UNI, how much of your relationship we’re you actually together?
The fact that your relationship never had the chance to cement itself by your togetherness, you need to just tell him. You could say you weren’t sure initially anyway with him being away most of the time and you didn’t know this but you need someone more local in your life. You could go on to tell him all the great qualities he has and that it’s best for the both of you and add, he’ll be meeting new people at uni and you don’t want to restrict that on him.
How long had you been dating before he went away to UNI?