That does suck.
I think sometimes people react/don't react to things because they're scared. They don't know what to do or are afraid of doing something wrong. Not always, but probably more often than we'd imagine. Still, it's hard being on the other end when someone's in a mode of not being able to handle (or even recognize) how they're feeling, because it can come off very badly!

Do you have a therapist? Have you talked with them about it? There are some strategies to help not internalizing as much, and they could be really helpful. Because it's awful to feel like that. Been there.