It's not a "gay song" per se, but "I belong to you" with Eros Ramazzotti and Anastacia is one of the most beautiful songs I've heard. If I ever get married, it'll likely be played at some point during my wedding. The singing doesn't start 'til 0:15, and the English doesn't start until 0:49. This is from a German TV show--the original video isn't available in the US. 
http://www.youtube.com/watch?v=SGNLvW3EZzs
http://www.youtube.com/watch?v=SGNLvW3EZzs


, now don't be greedy -- just get your fuckin' hug and pass it along for the next person! 