I find family can just push that button that leaves you feeling small and back in a place you don't want to be and it can feel like all your hard work never even happened.

That's why i severely limit my time with them. I get no nourishment from any of them so my boundary and gift to myself is that I don't need to put up with their behaviour. I will tell them not to say or do a thing to me and i expect it to be respected and if they can't respect it, then I take myself out the situation. I sound strong but i fall apart in private and am really affected by them but at least I'm putting in the boundaries and hopefully their behaviour will at least be modified in future.