You and your girlfriend have packed a lot of concentrated and heavy emotion into the time you have been together and I think the reality of it that you have been trying to handle all this when you are still effectively, a child. You have not had the opportunity to go gently into a relationship and learn how to be friends first and wait a while. Instead rushing into a sexual relationship, which has included an abortion, has forced you into dealing with emotions you are not yet mature enough to deal with. Even an adult would have found this difficult. You need time and space on your own to discover what you want to do with your life. I think you need to have a pleasant birthday week-end together but agree that you've both projected yourself too young and too heavily into a relationship which wasn't ready for the adult things it had to face. Talk together about some objectives you can both set for yourselves which will allow you to stay friends yet grow emotionally as you both need to do while you are apart. Take this learning experience into your new studying environment. Make lots of friends and learn how to handle other relationships but don't commit too deeply to anybody of the opposite sex. After a period in the emotional hothouse, you now need to develop yourself in a more temperate climate.