It depends on how badly that person has hurt you, though carrying grudges are destructive, some things cant be forgiven or forgotten about.
marry my first wife, then you will understand
Can I blame my star sign?...
i don't know
self absorped. people you hold one against have forgotten all about you!
Inability to forgive, bitter and twisted.
Fear and STUPIDITY!
I would say that, for some, it’s an inherited character trait from following in the same footsteps as others. There are those who derive a rather disjointed pleasure in doing such. There are yet others who’s lives are hard and bitterness is their best companion and they take what they love best to the grave. It’s hard to consider that a person can be as you speak of here, but such people do exist and I spent enough years watching a person do exactly what you say here. In the end it leaves the more sensitive of us pondering on why people should be like this and it makes us wonder why they waste their lives in holding grudges. The more sensitive people might find themselves grieving fur such people; I don’t see that as flawed, I see it as a person grieving the life of a person who was lost to the grave before their allotted time.
Still … such sad people exist and so are such people :-)
Grudges are what keep them going and keep the hate toward that party or person.
They are selfish they have no feeling for the one there holding it over!
Who every hold a grudge is childish and immature!
It makes them "happy?" lol, who knows?