Aha. I misunderstood your question (not that I'm the OP or anything)...
OP, it sounds like you're concerned that since most of your life is centered around being at home, that maybe you don't bring enough other interests to the table? I think Marcus' question pokes at this a little bit - if you find stuff to talk about with hubby, then you probably have these same interests to share with anyone else as well.
Honestly, what you provide to "the lifestyle" is YOU. The person you are.
(And honestly, I don't feel this is a Poly vs. Mono thing - I'm sure some single, mono parents feel the same way)