Listen to genetic. Her post is more helpful.

I think it is healthy guilt.

You feel bad for things you've done and want to take responsibility for those actions. Regardless if it is mental illness doesn't change the fact that her feelings were hurt and you feel bad for it.

I would write a letter and explain your feelings and what transpired instead of talking to her face to face. At least you will get to explain everything without getting tongue tied or misrepresenting anything. You can write the letter and post it and we can give you feedback.