I'm living with a couple of friends that are married, yet I am very attracted...

I'm living with a couple of friends that are married, yet I am very attracted to the female. She is very attracted to me but does not seem to be happy and I'm really confused. Any ideas?

Don't go there. In this case, the attraction should remain strictly an attraction.

Each attraction isn't meant to be acted upon. With feelings like the ones you have, it's high time for you to begin looking for your own place to stay.