Do I stay or do I go

Boyfriend moved 3 hours away, he is bi and does crave guy attention sometimes (hasn't told me but I can tell he likes it and missed it) I caught him on tinder about a month ago. I feel so down all the time and I think it's because of him. we get on so well and he's my best friend. I want it to work so much but I can't get over it. What the hell do I do?