Lama Ole’s answer:
What did Buddha say to that? If you want to kill a person, then you should consider that you’d actually only kill a corpse. Within a very short time, the person would have died anyway—perhaps they are already seriously ill. It’s not worth the trouble and doesn’t make any sense.
And what would I say? I’d say the best thing you can do is to forgive people. If you forgive them, you don’t have to meet them again in the next life—the bond is gone. If you hate people, then they show up in the next life; they’ll be just as odious and you’ll have to work with them again. So I always think, forgive them quickly, wish them all the best, and be happy that you can get away from them. That’s my advice—except when people come to you for help. Then you have a responsibility for them.
Also in relationships, I always advise separating on good terms. When people split up as enemies, it’s as if all of the experiences they had together are frozen—they have no access to them. Then in every new relationship, they’ll have to go through the same dramas, tragedies, and fiascos again. If people separate as friends and wish each other all the best, then they have their hands free and can do what they want.