Heather Locklear discovered "provacative" email that pushed her towards divorce

Heather Locklear and Richie Sambora were working through a rough patch
in their marriage, due mostly to the strife of two busy careers. Then,
sources say, a suggestive e-mail sent to Sambora by an acquaintance of
the couple became a final straw in Locklear's decision to seek a
divorce, PEOPLE reports in its upcoming issue.

Locklear found the e-mail, which contained "provocative pictures" of
the female, a close friend of the pair tells PEOPLE. Though the woman
had long been "a sore subject," says the source, Locklear never thought
she and Sambora had actually been "romantic."

Whatever conclusions Locklear has now drawn from the photos, they were,
her friend believes, the deciding factor. "She's devastated," says the
friend. "Absolutely devastated."

Sambora, meanwhile, is as upset by the photos as Locklear, according to
their friend: "Richie's saying nothing ever happened, that he never
asked for the pictures."

Another source close to the Bon Jovi guitar player says the photos are
neither the cause of the breakup nor indicative of a liaison between
Sambora and the woman. "It's absolutely not true that they had an
affair," says the friend.

Many observers believed the bond between Sambora, 46, and Locklear, 44,
was strong. "I thought they were the perfect couple," says their
longtime friend, music journalist Lonn Friend, who insists Sambora was
not your typical rocker. "He'd sown some wild oats in his day" but
since hooking up with Locklear, Friend says, he'd become "a family
man." The couple have one daughter, Ava, 8.