The following are not worth one second of ANYONE's precious minutes on this earth:
Guilt- Wallowing in it, either as a giver or a getter is pointless. Even dipping your pinky toe is worth niente, nada, zip, jack, bupkis... however you want to say it. Same difference.
Regret- Useless, learn and move on
Whining- Goes along with regret, no one want to hear it.
Pity- Insulting all around
Nagging- You can't care more than they do, believe me, it never works. Unless you do it because you love the sound of your own voice, in which case it's a sport, and I know some Olympians.