Girlfriend wants/needs to break up with boy-19. in love relationship for 5 yrs. Afraid he will hurt himself.?

A year and a half ago the young man developed an as yet undiagnosed run of mental illness's. Psychotic episodes, followed by meds then depression, and suicidal thoughts. hospitalized and now so very sad in his slow recovery. Has lost most of his amazing gifts for life. his art, his music, his unusual view on the world. He feels lost and boring and erased. She is graduating high school and has her sights set on university- medical school. Lots of promise. She loves him but the mental and emotional anguish is destroying her. She wants to leave him, so she can move on because even choosing any university outside of our town is impossible. He has to stay here for the time it takes to adjust to medication under medical supervision. He is not ready to live alone. But the painful decision is impossible to make. She fears for his safety and has tried to end it, but suffers not knowing what he will do. She makes the decision then it hurts her so much she calls and they talk all night until try again. I am the mom of the son. This is a hellish situation. i don't know whats best for anything anymore. She stays he is happy but goes through a roller coaster of emotions. If she goes do i say one clean cut and support him. She will grieve, but if she were my daughter i know that this situation is an enormous burden for her. She can not go the distance. He feels even more of a failure because he cannot meet her expectations, or be who she deserves at this time in his life. We can't possibly know what is going to happen with him in the future. The doctors and his team all say the road to recovery is a long long road, full of back stepping. That the dilemma I am addressing today. There are many things to consider and many other area`s of concern. But lets see what this brings.