I found my lost Wilburys CD this week, and with it I had the realization that this has happened for me: not with a romantic relationship, as the locked post implied, but with a friendship. One person and I had different ideas of what trust and friendship meant, and I was very hurt to find that out. But it was years ago now, and the song on this CD that very specifically associates with this person isn't bittersweet any more. I smile at the memory, and the smile doesn't twist, and my heart doesn't twist, either. I've always been friendly with this person -- so different from being friends! -- so it's never an issue of knowing I could be civil. And I still wouldn't confide anything of any depth in this person without significant time rebuilding a friendship, if then. But when I think of him doing something fun, silly, funny, I can smile. I can value the things that made us friends to begin with, without being blinkered about the things that ended the friendship.
This is a good thing.