Lyric discussion by bkabbott 

Cover art for Kick Drum Heart lyrics by Avett Brothers, The

At the end of the song the kick drum or bass drum whatever it is slows down. It seems to be imitating a heart beat. I think it slowing down represents the dulling/slowing of the people's feelings towards one another. People rush into marriage. I feel like when you're with someone that long you fall in an out of love and it requires a lot of work to make it work.