I agree with some of the previous posters, she seems to have lost interest in you. She may cheat to get out if you don't take her cues. 45 min is not so far and if she were really into you, she would be glade to make the drive. When a partner says they need space, believe them, they are puling away emotionally.
It's painful but I think it is best for you to stop seeing her before she does something to hurt you further. Break it off completely. You are going to a new school so you can heal and start over. IN time you may be happy things did not work out with her.