I can relate. I've felt that way. I'm interested in hearing how it works out for you. If you don't mind me asking, how old are you and do you have kids of your own?
When I was in your situation, I didn't really care too much about being "out" or not out to anybody. I didn't crave a traditional family relationship either, because i had a long traditional marriage and i already have kids. What I DID pine for a little bit was "family-style" time (e.g. going away for a weekend, cooking a meal together) with my lover. I wouldn't have needed alot of that kind of time... just occasionally. One weekend every quarter would have been perfect.
and I can see what GalaGirl is saying about being a "mono, but poly-friendly" person. This is what i believe I am. I tend to be pretty happy with one partner at a time, but I don't feel the need to be that person's only partner, and it's very important to me that my partner be open about his other relationships.
I think it's probably much more productive to think about what kind of life would make YOU happy (and what's missing) instead of to fret about whether or not you "are poly".
Leelee, all alone.