I want to break up with someone who needs me. How do I do it with minimal damage?

I am struggling with feelings of guilt. I have been with my 22 y.o. boyfriend for 2 years. He has a lot of physical medical and mental health issues, which I’ve been happy to help him with. I probably spend 70% of my time supporting him. I honestly feel like I’m with his caregiver more than his girlfriend. I am very concerned about him and the idea of leaving him, because I honestly don’t know if he can function without me. I love him very much, and he would be devastated if I left. I really feel obligated to stay but I’m burning out. I want to break up with him and move on with my life. I want to be happy and fulfilled in a relationship with healthy communication and healthy roles. I feel like I’m losing myself and the years of my youth and I can’t do this forever. However I feel so bad about it. I can’t seem to find happiness with him anymore. I don’t know what to do.<br><br>Tldr: boyfriend is very very sick, I probably need to leave him but he’s very dependent on me so I feel bad leaving.