Hal Jordan and Carol Ferris breaking up is a bad example. I don't think anyone is going to get too upset about this. Hal and Carol have been breaking up and getting back together since 1965. The only reason to complain about it is that it's a tired old idea.
There are a lot of tired old ideas in the DC universe that keep getting recycled. And if you've read the comcs long enough, you start to notice this and get cheesed off when yet another writer tries the same old thing. The fact that the characters keep getting rebooted and retconned means that it has a chance of happening more often--with the characters themselves not remembering that they've been down this road already several times before.
It's only the poor reader who remembers, because he or she has all the comic books to prove it. Sometimes I think DC would like us to burn all our old comics, so we don't remember every time they tried to pass off a moldy oldy as freshly baked.