I wish I had a time machine...

Sometimes I wonder 'what if...'
What if I'd not done that, or chosen not to keep things the way they were? My life would be different, no doubt about it, but good different or bad different? How different? Obviously there's no way of knowing, and I feel guilty for even wondering about it, but I do anyway.
I feel bad for hurting that person, I still remember that look, and even if I was brave enough to say it to their face, they'd shrug it off, pretend it had never even bothered them. I know it did, and I am sorry. But I still wonder if I hadn't been so shallow, how great might it have been?
Sometimes they say things happen for a reason, and it might be true, but I don't think I'll ever forgive myself for the way I handled that situation.
I don't really know why I'm writing this, the person I'm referring to will almost certainly never read it, and even if they did, they'd probably think it was about someone else.
Sometimes I wish I had a time machine...