hey guys! i really dont know what to do right now and could use some advice/ encouragement.

i have really bad ptsd from my dad walking out on me when i was a kid. we would get into an argument and he would storm off, get in his car, and leave for hours. i never knew if he was coming back or not. my boyfriend has done the same thing to me about 3 times in our 1 1/2 year long relationship. the last time he did it he promised me he would never do it again. this past weekend he stormed out again and when i asked him if he remembered that promise he made me he said he totally forgot. i know he made that promise months ago, and hes very forgetful in general. i just think that something that important to me would also be important enough for him to remember? hes promised (again) to never storm out again. i dont want to be too hard on him because i dont want to discourage him from working towards changing things, but part of me feels like i need to crack down a little bit more. this is the first time hes forgotten one of his promises.