You feel like you crossed a line by actually self-harming and you are not sure that she will want to be with you on the other side of that line. I would guess that it is similar with suicide?: if you were to attempt, you would worry that she would not stay with you then either?

It sounds like you experience a lot of shame, and have for a long time. I'm really sorry for that, and for the pain that it brings you.

I wonder if she is aware of anything that you have done that feels shameful to you. I'm not asking what those things (if any) might be, I am just wondering if she is already aware of you doing something that feels shameful to you. If she is, how did she react when she learned of it/them? How has her knowledge affected you relationship with her (if at all)?