For what it's worth, from a father of three... my ex coddled the kids in this regard. She _demanded_ absolute silence when they went to sleep. The problem is, that _trains_ the kids to need absolute silence, rather than getting accustomed to hearing the occasional sound and putting themselves back to sleep. The best things you can do, for your own well-being and theirs, is let them cry it out a bit and go about your normal routine.
I must admit we have a divide like that too. My wife will stir at the slightest noise, whereas I assume that a murmer or two is just a random noise and safe to ignore.
Obviously if the baby is crying heartily either of us will investigate, but I don't feel the need (most of the time) to check on him if there are sporadic gurgles, laughs, or "noise".
That said I think my wife is coming round, she's started sleeping with earplugs now so that she doesn't wake up unless there is a real "emergency".
(I wonder if you're getting downvoted for mentioning "cry it out"; the only thing more controversial in parenting is circumcision.)
Yup. We live in New York. There's no such thing as absolute silence here, and she can still hear things from the living room. We're definitely not requiring silence :P
