I agree with Sachs why would you stay if the love has gone (hehehe sounded like the song lol sorry)
If its just the physical your after get a f*ck buddy...
I know I might sound a bit old fashioned - and I am only 35.. but you married him/her.. so I assume you were in love... and I also assume that for some years it was lovely... why cant you work this out?
He/she should be your best friend... talk.. get counselling... dont just lie back and accept a loveless marriage - if it was once there you can get it back!
Nosha you are not old fashioned that the way it works, you get married and your so deep in love and your partner should not only be your lover but your best friend too you should feel comfortable to do so... I am only 22 and have been married for less then a year but together since we were 16 and let me tell you the most beautiful thing is when we can sit and talk about ANYTHING... u should try it :)
Depends on the circumstances ianess. If the love was going out of my marriage - I'd want to know why! I certainly wouldn't look elsewhere unless the marriage ended.