I may be a little infatuated with my housemate! help me please!?

I have a new housemate. He moved in 3 weeks ago and we immediately clicked, He is funny and good looking. We like spending time with each other and we are often quite affectionate. I can't stop thinking about him, It is really frustrating for me though as I know that he is a huge flirt, and I would never date him.What can I do to get him off my mind! I lie in bed thinking about him and its driving me crazy!!!!