Sketchy and really dishonest, but not an uncommon situation for people who go into college maintaining their high school relationship.
College is the place you explore your personal boundaries to figure out what kind of person you are going to be. It's impossible to do that if you are still bound by something from your high school years, and inevitably, 999 times out of 1000 either one or both are going to do that exploration behind the other persons back, or one or both will grow to resent the other person.
I fully support people staying single at least the first couple of years of college till they get some of that out of their systems. Even longer, for most people, though I know that's not always realistic. I think it's good to have the freedom to choose the direction your life is going to go, the place you are going to start your career, etc without having to make sacrifices for another person that early in life. Those years should be about you, your personal growth, and having the freedom to make choices based on what YOU want for your life. Then you open yourself up to someone who's on a similar track.
I'm sorry you are going through this, it must hurt like hell, and it sucks when people you love don't give to you what you give to them...but at least you found out so you won't waste any more time on someone who isn't committed on an equal level.