The singer has been placing personal calls to all of the editors of the major celebrity weekly magazines in the US to apologise for Shuter's actions, which culminated in a recent cover story in People claiming she had found love with Mayer.
Simpson and Mayer have since called off their relationship and insist that the media coverage surrounding them was exaggerated and they are actually just good friends.
The calls to the editors are being supervised by a publicist from her record label Epic and a remorseful Simpson is reportedly expressing her gratitude to the magazines for supporting her career and telling them she would like to take on a more direct role in dealing with them.
A source says executives at Us Weekly, Star and In Touch magazines were happy to speak with Simpson, but People editor Larry Hackett hasn't been as readily available.
According to the source, Hackett is still furious that his magazine was used as a pawn to report Simpson's non-relationship with Mayer.