Divvy up responsibilities around the house.
If you say anything about a woman’s place being in the kitchen, we'll slap you for her. No, seriously, moving in with her doesn't mean she instantly takes on the role of your mother.
Share all responsibilities. Figure out who does what based on preference, not assumed gender roles. She’d rather take out the garbage than vacuum? You like to cook but hate doing dishes? Figure out what makes sense, and be appreciative of one another's efforts.