That's the really hard part with brain damage, it really is a case of getting stuck, I think you described that perfectly. For me it feels a bit like being a record & the needle gets stuck on repeat because the next bit simply isn't there & I may not realize it until I'm being yelled at for repeating myself.
Anger & the resulting shame are awful on the brain & can really cement branches prone to depression. That's why I try to shake it up, so my inner voice is like "oooh, good job you went to your appointment!" & even if I feel all the feels of 'well this is bullshit' & rolling my eyes, I usually end up laughing & the thought didn't go in it's usual direction & I can start figuring out what's derailed me until I reset, yet again.