Letting go of hurt

Can you let go of a 30 year old hurt? I'm trying. It's not that I particularly want a relationship with the person who hurt me, I just think it's not good for me to carry a 30 year old hurt around. But it's hard. It's freakin' hard. I still want satisfaction. I still want her to know she failed me when I need her. I guess the thing is - I need to let it go for me, not for her. I don't want to resume a friendship with her, but I can confirm her friend request on facebook. After all, I am facebook friends with people from our high school class that I never hung out with back then. It would be hard to say no to the person who was my best friend all through high school. But being a facebook friend is as far as I'm willing to let her into my life.