I don't hold onto the past, I'm not nostalgic at all, and I think change is inevitable and welcome and perfect. However, I do have involuntary, gut-reaction, unpleasant feelings when a negative figure from my past crops up again. I may not even remember what exactly it was about this person that upset me so much, but the general impression returns and I want to run from it.
I've actually gotten myself burned pretty badly when I've acted against that sensation, putting my own feelings aside. I've tried to stay friends with people I knew that I shouldn't have, and the only thing it did was prolong a painful experience for both parties.
I don't want to hurt anyone or make anybody sad, and I am the last person to engage in acts of vengeance. I don't stalk people on Facebook, either. I just let them go.
But when I let them go, I kind of want them to stay gone.
I tend to move on quickly, and I'm usually pretty happy after doing so. My life gets better, I find more compatible friends, chase higher goals, etc., and I think the other person's life gets better, too. It sounds cheesy, but I think things happen exactly as they were meant to. Sometimes, if prompted to think about it, I actually remember a lot of the people I've removed from my life with love. I just don't have an interest in rekindling what we were - not even muted versions thereof.
One of those old friends has tried reaching out to me a few times in the last year, and it's sad, but I just can't bring myself to respond to her. Not out of a grudge, just...I know it's not for the best.
So, long story short, I don't hold grudges...but I think it appears to others that I do. It's really hard for me to keep a source of pain in my life. Maybe that's weak, I don't know. But I guarantee you there are probably a few people out there who would say, "Oh, her? Yeah, she HATES me," when in reality, I haven't thought of them in quite a while.