Look, having a baby is very big. You don't want to make people envious or anything, but everything else is peanuts. -- Jack Nicholson
Okay, so you feel a little superior. And a little sorry for people who haven't experienced the wonders of pregnancy and parenthood.
There's just no way to make anyone who hasn't been through it understand how "big" it is to have a baby. And even if you could, you wouldn't want to make others feel bad about what they're missing.
There's no reason to avoid friends who are having trouble conceiving or who have decided not to have children. Do your best to be sensitive to their needs. But remember that their support may be limited. Make a point of seeking out other expectant and veteran mothers with you whom you can really carry on about what a big thing this is.
Affirmation: I can share my pregnancy without compromising my friendships.