I've asked this question twice
The first time, I didn't really believe that we could be friends. It was all too upsetting. He went for France for a year and we barely kept in contact.
However, we're both now, 2 years later, in a place where it doesn't hurt to see the other. My memories make me smile as opposed to feel sad; it's a place I never thought I'd see.
He's now at University with me again and it's great having my friend back. I'm truly overwhelmed that this person who I hurt so badly would still want me as a friend. That's the kind of friendship that lasts a lifetime.
The second time... well, we'll see.