Advice for letting go of grudges?

I’ve had a couple grudges holding me back for years. Two people close to me broke a promise and also ended up taking several of my belongings and throwing them out, some of which are irreplaceable. My minds been made up what would need to happen for everything to truly get better and me to move on but that’s pretty much impossible. Lately they’ve been weighing me down and impacting my life. I’ve been working on alternative solutions to the issues but it’s not really helping as much as I’d hoped. Any advice on how to move past these grudges or let them go finally?