| NY is a big place, so I wouldn't go trying to point out a specific church, but I would suggest trying to find a Unitarian Universalist church. My dad (wouldn't call him agnostic, but I don't think he even knows what he is) pulled me along to a new UU church in our community (under the advice of my scout master, who was concerned about my pagan belief structure at the time). It turned out to be the most loving, open, and diverse place I've been, nothing like the stuffy church I used to go to with my grandparents. It probably wasn't what my scoutmaster had in mind, but it was really the perfect place for me. They accept people from all different religions (our congregation had christians, pagans, hindu's...) and their message is more about doing good deeds and acceptance of others. Even my mother, who had bad expiriences with the church when she was younger, although still identifies as a catholic, enjoy's going.
I'm an atheist now, and I'm still an active member of that church (or I would be if I wasn't overseas, but I'll get back to it) It's just a fantastic kind of community that the UU's present, and it seems like you and your fiance would be a perfect fit.
__________________ "We can easily forgive a child that is afraid of the dark, the real tragedy is when people are afraid of the light"
-Plato |