"Tom and I like being able to walk around naked," the Hot in Cleveland star, 50, says in the March issue of Good Housekeeping.
But the couple's uninhibited pastime isn't always possible. "You can't [be naked] when the kids are in the house," Bertinelli says of Vitale's four children from a previous marriage and Bertinelli's son Wolfie, with ex-husband Eddie Van Halen.
The actress's comfort level with her husband, 49, is more than skin deep.
"He has unlocked some things in me that I usually like to keep buried," Bertinelli says. "He unlocks a lot of the stuff I don't have to hold on to anymore … I love him. I adore him."
Even though Bertinelli couldn't seem happier or more comfortable in her current situation, the Jenny Craig spokesperson – whose top weight was once close to 175 lbs. – isn't letting the ease of marriage keep her from maintaining her bikini body.
"I have to wake up 40 minutes earlier just to get on the treadmill so I can run two and a half miles," she says. "As long as I wake up and get my workout in, I'm one step closer to having a good day. If I sleep in and don't run, I'll feel a little bit off because I didn't do what I was supposed to do."