I must admit when I was younger I was a bit like this. I would fall into resentment and let people bother me over the long term but that only ended up harming me more than it did them. These days I will let a lot go, mainly because I don't care enough what they think and am more than comfortable with who I am but on the other hand, I'm also far more likely to just confront someone and escalate the situation immediately if they really push things too far.
That's been working out well for me so far.
I don't believe in grudges. Never held any of them, but had an ex that made a habit out of it. Only in her case she always did something about her grudges. In a way, I admired that in her because I was hopelessly non-confrontational by comparison. Something bothered her and she acted to change things albeit with a time delay and a toxic period of growing the negativity. But that kind of conflict causing behavior is just war by another name. I truly believe women are more prone to warfare. If a man has any courage and foresight he will resolve an incident that would lead to a grudge in the present. I think grudges are like a pressure bomb. Building and escalating past the point of failure. Ensuring an upward spiral of destructive acts between each party more severe than the last. Plenty of time to plan in between. Noble conflict resolution is immediate and does not plan to persist or grow.