"About a year ago I called him on his tour bus and heard giggling voices in the background," she tells Glamour in its July issue. "After that I said, 'No more girls on the bus.' "
Still, the Knocked Up star, 28, is looking forward to having kids with Kelley. "I hope to have children and the sort of family traditions where we eat together every night," she says. "Joshua will be amazing father, so I won't have to do it alone."
Part of what keeps their relationship strong is their common perspective, she says, explaining that they "see very eye-to-eye."
And she isn't really threatened by those groupies – especially because she's comfortable with her body. Though she tells Glamour she had to lose 10 lbs. for her Knocked Up role – achieved with rigorous exercise and a strict diet – she adds, "I could never maintain it. I like food too much!"
(She recently shared her workout tips with PEOPLE, and said: "I'm in the best shape I've ever been in.")
She also reveals that she admires Jennifer Aniston, Halle Berry and Kate Winslet for their healthy attitudes about their bodies. On Winslet, Heigl says: "Early in my career, I read an interview she gave about how the industry wanted her to lose weight; she basically gave them the finger and said no. I remember thinking, I can do that too. I don't have to look like one of these genetically superior people in order to work."
While Heigl has already publicly forgiven Washington, she tells Glamour that she still feels strongly about the situation. (She was interviewed before ABC decided not to renew Washington 's contract.)
"That particular incident really infuriated me, and I couldn't hold my tongue," she tells the magazine. "I think it's pathetic there's still so much bigotry in 2007, and I would speak out again if the situation arose."