Lyric discussion by TheTANK 

Cover art for Love and Memories lyrics by O.A.R.

The person who said that the song was about the movie "Eternal Sunshine of The Spotless Mind" is correct. Here's the direct quote, Marc Roberge himself explaining the song:

"When writing music I think it is important to take your headspace and relocate now and again. This song is done in character. Put yourself in the movie" Eternal Sunshine of the Spotless Mind" as you watch yourself rapidly being erased from someones memory. That is what this song is about. It is intended to be a first person account as this man watches the love of his life dwindle away in front of his eyes. Or is he dwindling away as she pleads with him to stay with her? "

from: http://oarsa.org/features/viewsong.php?songID=143 (the O.A.R. setlist archive)