Just generally a case of past screw-ups that ruined relationships (of varying kinds). In some cases I regret something I did, in some cases I'm just annoyed that things were never truly understood, be it by me or someone else.

I think I can still mend some of these if not all of these, but either it's a risk of opening up old wounds, or it feels rather trivial and not worth talking to someone out of the blue about it. In either situation I also worry that it'll come across the wrong way, like I have some kind of ulterior motive (and with perhaps one particular person, it probably would indeed have one, whether I wish to admit it or not).