I just have to say reading your post reminded me so much of my ex, especially the parts about him demanding flexibility after the fact, using the good things you do against you and his expecting you to remind him. Those are the exact behaviors my narcissistic ex takes part in.
I think it is funny because narcissists think they are unique, one of a kind, yet they have the exact same bad behaviors.
I've nothing to add or advice to give. I just wanted to let you know you are not alone.