I think it is about falling in love with a promiscuous girl. A red dress is synonymous with sex appeal, "In a red dress and alone" makes you think about an attractive girl that loves 1 night stands. "I am not the only one" implies he has realized he is just her latest victim. "But her beauty fades when she dies" does not literally mean that she dies, but more coming to the realization that the one night stand meant nothing to her.
In the beginning of the song "Let's start it over, from the beginning, let's play for keeps so I know you can't get the best of me", he is reflecting on this girl, and wishing he had a mulligan, so he would not have been so foolish to fall in love with this girl.
I think it is about falling in love with a promiscuous girl. A red dress is synonymous with sex appeal, "In a red dress and alone" makes you think about an attractive girl that loves 1 night stands. "I am not the only one" implies he has realized he is just her latest victim. "But her beauty fades when she dies" does not literally mean that she dies, but more coming to the realization that the one night stand meant nothing to her.
In the beginning of the song "Let's start it over, from the beginning, let's play for keeps so I know you can't get the best of me", he is reflecting on this girl, and wishing he had a mulligan, so he would not have been so foolish to fall in love with this girl.