Notice how all your removed posts were on Beehaw. Beehaw has extremely strict moderation. This is their reason for existing. It is not personal.
That said, you do not ever need to explain an absence, and it is in fact kind of weird that you feel you need to "finish" things. Nobody is grading you, and it's very unlikely anyone is even missing you. That may seem cold, but it's the reality. This is an anonymous internet forum. Nobody is specifically mourning how much they miss certain individuals here on a daily basis or frustrated that a conversation didn't continue further. That's just not realistic, that's not how it works. Maybe that's how you want it to work but if so, you're in the wrong place for that. (I don't know where the right place for that is but I am pretty sure it's not here)