TIPPER GORE‘s jealous rages over other women ripped apart her storybook marriage – and prompted her husband AL to pull the plug on their 40-year union!

According to multiple sources who spoke to The ENQUIRER, that’s the untold secret behind the shocking split of the former vice president and his bubbly blonde wife, who stands to get up to $250 million in their divorce!

"While there’s never been proof that Al had affairs, Tipper allowed herself to suspect the worse," divulged an insider close to the couple.

"I think she’s always believed there was something going on between Al and many of the women in his life."

Those women included an environmentalist named to a prominent cabinet position by Gore when he was vice president, a sexy Hollywood actress, a gorgeous massage therapist – and even his first love!

Gore, 62, married Tipper, 61, in 1970 after they met five years earlier at his high school prom, and Tipper’s jealousy stretches all the way back to his childhood sweetheart Donna Armistead.

When a whispering campaign linked Gore to a sultry screen star in 2001, "Tipper confronted Al about it, and he denied it," said a source.

When she learned of rumors about a liaisons with a Tennessee Titans cheerleader, Tipper went on the rampage, lambasting Al with unfounded charges.

"But by this time, Tipper’s jealousy was putting stress on their marriage," the source said.

"Al finally told her their relationship was over because he couldn’t stand her jealous rages anymore."

You’ll find ALL the details only in the ENQUIRER – still on sale.