Throwaway account just in case.

About four months ago, I (M18) asked another guy (M19) out. For the sake of simplicity, we'll call him Sean. I'm openly bisexual (my parents were very loving and accepting despite their southern beliefs; don't stereotype, kids!) and I had a crush on him for about two months before working up the courage to tell him I liked him. We talked about it and decided to start dating. 

Sean is a closeted bisexual and is dead-set on the idea that his parents would immediately disown him on the spot and informed me on one of our first dates that he was "not out and had no intention of coming out to [his] parents in the future, ever." For someone who spent a multitude of years hiding their sexuality from their parents, I loathed the idea of keeping our relationship a secret. However, I liked him so I was willing to wait things out and see how it went. 

About two weeks passed and I started to feel like I made the wrong decision. Sean had a lot of emotional problems occurring at home and pushed a lot of that onto me. I still gave it a chance though, as we were only two weeks in.
It was exhausting, however, because I was also dealing with escaping from a very emotionally abusive friendship and all of these factors left me drained. Even as I knew the relationship wasn't going well, breaking up with someone added on anxiety so I figured if I waited, maybe I'd regain the feelings I felt at the beginning. 

My university let out for winter break and I was struck by the full-force realization that things weren't going to work out between us- and to make everything worse, I realized that I had a real crush on someone else (20F) that felt truer than any emotion I felt for Sean. Since Sean lived about five hours away from where I was staying for break, I steeled myself to end things with him as soon as winter break was over. But the moment I got back, I was slapped in the face with a multitude of legal battles against the person who abused me the semester prior. Under the stress of fighting to get a restraining order and coping with the anxiety that comes along with having a stalker, I simply could not bring myself to break up with him.

Now he is opening up about his innermost anxieties and talking about a future together- which would make me uncomfortable even if I was in a long-term relationship (I'm 18, I'm more worried about keeping up my grades than my future family). I don't think I can keep this up, but he is so emotionally reliant on me that I'm worried he's going to hurt himself if I break up with him. I feel like I'm the asshole for letting things get this bad even though I had other stressors to deal with. Am I?

Side note: Sean has been telling me recently that he experiences a lot of homophobic thoughts, going as far to say how he thinks his life would be much easier if he was straight (before quickly following it up with "I feel so guilty saying that to you") and its taking a toll on my mental health.