coping with nightmares

i apologize if any of this sounds frantic, i have just awoken from said nightmare and i’m distressed lol.

my question is, how do you cope with cptsd related nightmares, specifically ones that apply past trauma to your current life? for context, i just had a dream that my current boyfriend, who is actually lovely, was emulating the actions of a past abusive relationship. specifically cheating and gaslighting. i woke up next to him and didn’t know what to do other than run out of the room.

it’s one thing to dream about the abuser that’s already gone. it’s another to dream that a safe person is becoming an abuser. i know it’s not true, but in the moment, my brain can’t tell the difference. any tips for coping with this?