Have you ever been angry because of someone/something that you know you probably shouldn't be, but you couldn't let go of it anyway?

The type of situation where you are 100% positive you are being oversensitive or overreacting, but you can’t stop being angry anyway?

I feel like that right now, and I feel very stupid for being angry, but I can’t make myself feel better either. I want to vent, but I don’t want to sound like a whiny, bitchy, entitled person either. Maybe if some nice people who have dealt with this effectively would share, I could feel better! :D