I have a girlfriend but like another girl - help please!?

As awful as it is for your current girlfriend, if she has said that she 'doesn't want to give long distance a try' then she obviously isn't going to make an effort when you move away either. I would tell the other girl how you feel and let her know that you plan on ending it with your girlfriend when her exams are finished. Don't do it before, you will mess up her future and that's not fair at all. Don't cheat on her with this other girl but still talk to her and let her know whats happening. If she likes you back then great! After exams finish with your girlfriend and start dating the other girl, keep it light though for a few months so you don't jus look like a jerk