So I get home and notice that he didn’t move his things in the other room. OK so I never answered your question. You could have still taken the initiative to move your things into the other room.
Does this refer to the MBR? The other way to look at this inaction is that that space is YOURS now. He is viewing it as yours, and to enter without express permission would be crossing a line. Perhaps he's being passive aggressive, perhaps he was being lazy or trying to push your buttons. But from this moment forward, that space is your space and the room he is staying in is his space. I would vote that you don't enter either one without a polite request. Other areas are common areas, but I think you both need an area you can retreat to without fear of the other person entering.
