What if you transferring M fears onto the library book totally? And you don't fear his yelling so much anymore as you think (you can walk away. you have a method to escape it) and you are sheerly having a panic attack about whether the R is going to work out?
If this is true, what can you do about it besides self soothe and not beat yourself up? I don't know. People can say detach, detach a lot, but it seems difficult to do that in piecing when you also need to be emotionally there quite a bit to do it right. Maybe you were tired today and that also contributed to the panic.
I would reframe yourself as more in control than you think. Yes, you had a panic attack but you did not let the panic attack control your behavior and freak out on H. Congrats. Yes, you shredded a library book. Who cares? Reminder to check for next time and move on. Congrats on moving on and not obsessing about it tomorrow. Yes, you're not perfect and neither is your H. Welcome to being human. Congrats.
Maybe living with H's rigidity in all things is a topic for IC in the near future. I agree with FM's stuff about your internal story. You are now living in H's bubble that stuff that is "big" to him is "huge" in the scheme of things. No, he's just rigid. Misplaced computer cords and messed up library books will occasionally happen. So how can you live with a rigid person without getting sucked into the fallout or worldview of their rigidity? What are the techniques not to take on their feelings, if there are any? I don't know. Ask IC.
I don't like your panic and negative internal story. But I like that H didn't rage up and that this was "only" a panic event which gives you a clue for something you can work on.
