When you think about it, Al Gore was already in love with someone else -- Al Gore. There was no room for Tipper in his life ... or in his $9 million mansion.

From The Associated Press:

Former Vice President Al Gore and his wife, Tipper, are separating after 40 years of marriage that included a White House run when their sunny relationship offered a counterpoint to President Bill Clinton's philandering.

According to an e-mail circulated among the couple's associates on Tuesday, the Gores said it was "a mutual and mutually supportive decision that we have made together following a process of long and careful consideration."

Gore spokeswoman Kalee Kreider confirmed the statement came from the Gores, but declined to comment further.

The Gores were telling friends they "grew apart" after 40 years of marriage and there was no affair involved, according to two longtime close associates and family friends, who spoke on the condition of anonymity.

The associates said the Gores, over time, had carved out separate lives, with the former vice president on the road frequently. One of the associates said: "Their lives had gotten more and more separated."