My mother has been a long time "hag/fruit fly/other term for a lover of gays" and this past October she officiated the marriage of two of our friends that have been together exactly how long my parents have been married. It was a small but fun wedding. Good luck and more power to you.
My life wouldn't be the same without all the gay "uncles" my brother and I had growing up so don't let anyone tell you it's any less meaningful.