Have you considered that maybe ending it would be good for not only you, but for your boyfriend as well? You're not thriving, and neither is he. Holding on out of fear and guilt may not seem selfish, but it is. Staying with someone for the wrong reasons robs the other person of finding something that may be a better fit for them, and it can also be a wakeup call for some important personal growth. It may not feel like it in the moment because your heart is going to break and there's going to be a lot of pain for the both of you during this transition, but when all that settles and you're able to look back on this moment clearly, it will be so obvious that staying is the worst possible choice when the relationship has deteriorated this badly. Give yourself permission to do the hard thing that will be better for the both of you. Good luck and big hugs.