i thougth of amy and dan “Love makes you want to be a better man—right, right. But maybe love, real love, also gives you permission to just be the man you are.” ― Gillian Flynn, Gone Girl
With regards to Dan, I think the only possible way for an adult woman to love him and not be completely steamrollered is to set very clear, strict boundaries for what behaviour she will and will not accept from him.
Being loved for who you are sounds great, but Dan, left to himself, isn’t lovable. He’s too consistently cruel and self-absorbed for that. If what we’re given to understand about the way he treats women is true, accepting that behaviour wouldn’t be loving, it would be masochism. Loving Dan demands that he make himself better, because that’s the only way he’s worthy of it.
It works a lot better the other way round, mind you. Dan certainly lets Amy be herself – it’s one of his few redeeming features.