I've given this some thought. We co-slept for the first 6-9months and then put ds in his crib. When we moved we went back to the family bed and we are still co-sleeping. I'm realizing we think we sleep badly because it's ds's fault sleeping like a baby and blaming co-sleeping etc... Well, dh has changed jobs, his stress level is way down and he's happier and we are all sleeping well!
I remember reading about co-sleeping and breast feeding before ds was born and they said that the mother and child would develop a connection from the closeness. That is definitely true. In the same chain of thought the energy from all the individuals in the family bed rub off on everyone else. So, maybe we all just need to de-stress with a relaxation cd or something before we go to sleep to get a good nights sleep.