Seriously, surely this is normal? DH just made his 'pained face' when I popped up to air the bedroom prior to retiring. Over Christmas I opened all the windows in my mum's and PILs' insanely overheated windows before going to sleep. I almost always have open windows to get fresh air whilst we sleep.
I don't know how anyone can sleep in a stuffy room with the windows shut all day and all night! DH keeps saying 'But it's December'. Apart from the fact that it's now January, isn't he BU??