Hello Katie,
Im sorry that you are going through a difficult time right now.
When I went to university, I had the same experience that you did in trying to make friends. Then I started to feel resentful about it, but knuckled down to my studies. Eventuallyy, I did make friends. Admitedly, I was likely older than you as where most of the people at my lectures and tutorials. I was ssurprisedto eventually learn that there were not all of these parties which I had imagined. Most students were so busy with supporting themselves financially as well as studying, and there wasnt the time or energy for parties though I cant know fot sure if that is relevant in your case. When I did make friends, it was through participating in various group assignments.
Regarding your boyfriend, that is unfortunate. Regardless as to whether you should have told him more, his response raises sone serious red flags as to whether he is mature enough for a relationship.