What is the Catholic Teaching of living together if your not married?

[erkie_gurl]

My boyfriend is Catholic, I am not. We have to fill out a questionnaire in order to get married at his church, and then six months of marriage counseling classes. I know his answer, I am just curious to what everyone else's is. If your catholic please answer, it would be awesome, if your not, I'd like to hear your side also.
Thanks
I understand what they think of two people living together, but i mean what do they teach you? I've heard some people say that they just want you to sleep in seperate beds...
He's not really devout...He was when he was little, but he wants to get married there because that's the church he's known and grown up in. I'm fine with it, and his parents don't have much to say in the matter. They know that we live together, sleep together ect. They are just happy for us to be getting married.