I don't think you have to be sexual to love another person. So as long as you and your husband are up to loving other people, I think you fit in the poly community.
However, I think you could just as easity fit into monogamous world. I think a lot of monogamous people have "BFFs" that they love. I think it only gets weird if the friend is someone the person COULD be sexually attracted to.
I think polyamory does help with theidea that one partner is not suppose to be everything for the other. They are just suppose to be themself. So one relationship could be for security and common goals in life while another could be for BDSM or extreme sports.
Hope you enjoy it here.