Sexy married woman around - had obviously stayed over.

My housemate seems to have been pretty good friends with her for a while - I am also acquainted with her as a result. Couldn't really fathom what's going on between them, obviously something dodgy though.

Once she was gone, my housemate apologised for 'the noise this morning' and I had no idea what he was talking about. I assume loud shagging was occurring as I took my morning shower.

Needless to say it's awkward and I don't know how to be. Please tell me how I should tone upcoming conversations.

(aside: I wish I still lived with indie virgins/ people in committed relationships)