How do I get out of this situation?

So I know you have probably all heard this a million times before but I really need some sort of outside advice. My girlfriend and I have been dating for almost a year, and while I do care deeply about her(more as a friend would to another) it’s become painfully obvious our life’s are going to end up in separate path’s as we are both young (19) and have different life goals. Also, I hope this doesn’t come off as an asshole way of thinking but I planned experiencing more than one serious relationship in my life. I would like her to still see me as a friend,but if she doesn’t it will be extremely awkward as we live together (stupid to do so young I know) and getting my stuff might be rather difficult. So my question is how would you go about ending this if you were me, accounting for the logistics of how to get my stuff , and we also have two classes together one of which involves a group assignment with the two of in the same group. Should I, if possible, wait until the semester is over or end it now because the emotional apprehension is literally making me sick?