How do i break up with my gf who’s done nothing wrong

I’ve been dating my girlfriend for almost 3 years now, we’ve been through so much together, but i just don’t see a future with her anymore like I used to. The only issue is that she feels the complete opposite. I know that I need to just rip the bandaid off and tell her, because it’s unfair for her and for me to go through a relationship that I don’t want to be in. But how should I do it? She’s away at college most of the time (like an hour drive) and I know I can’t do it over the phone bc duh, so clearly I do it in person but what do I say? How do I explain myself? I know she’s gonna cry which is what I think is preventing me the most. If you guys have any advice pls help me out here.