So first things first, we have been discussing moving in together, but although he seems to agree most of the time, there are some points when it seems like something is holding him back. I've asked before the reasons he doesn't want to (just trying to see if I need to change anything about myself, not trying to be pushy), but he always avoids it. My guess is that it's about his vaping habits, which he know I'm very very against. I have a history of respiratory problems, and being around any kind of smoking or vaping makes it really bad for me. The problem is, he's been doing this since before I met him, and so I know I can't change anything about it. I would be willing to compromise with it, like maybe just agree to not do it in the house and/or around me, to help my lungs. Is this the right course of action, and something I should bring up to him? Or would it be stepping out of line to bring it up as an assumption I made?