I am going through something frighteningly similar to you except that I am not married. We have been together for 9 years and if our friends and family would have it their way we'd be married already, however i've always pushed it off for one reason or another.
We get along great and he is really the perfect man and I know I love him, im just not sure im in love anymore. Our sex life went from wow to what?
I find myself attracted to other men as well and have cheated on my bf a couple times, always with good friends who've crossed the line first towards a fling. Im not proud of this, and on occasion I have lost the feeling of guilt as well by trying to justify that the affair was something to make me happy.
I do agree with missshortie that it is not fair to the husband/bf and that by cheating its ruining his life as well. My bf does not know about my infidelities, however he does know im not entirely happy in our relationship and we're currently discussion what we should do.
He loves me to death, but would rather end it than know I dont want to be with him. I havent decided either way yet, however I think I want to fight for us. I do enjoy the life he provides, who he is as a person, and all the great times we have. I know a lot of work needs to be done on my part to remain faithful to him and only him and im hoping i'll have the strength to work at it and ultimately be happy.
Its scary, thats for sure.
Good luck and just know your not the only one out there...Your so not alone.