Lisa Rinna on the Secret to Her and Harry Hamlin's 20-Year Marriage: 'We Have Nothing in Common'

Lisa Rinna is sharing her secrets to a happy, long-lasting marriage in Hollywood.

Appearing on Watch What Happens Live with Andy Cohen on Tuesday, the Real Housewives of Beverly Hills star opened up about her relationship with Harry Hamlin — and how they’ve kept the spark alive over the course of their 20-year marriage.

“I don’t really know. I really don’t know the answer,” she admitted. “I think that we are complete opposites. And I mean, we have nothing in common!”

“You know what you have in common that wildly comes across?” chimed in host Andy Cohen, 49. “You are crazy about each other.”

“We are,” said Rinna. “We are crazy about each other, and you can’t create that, you can’t make it — it either is, or it isn’t.”

Cohen asked if the bond between Rinna, 54, and Hamlin, 66, is stronger because they spend so much time apart due to their busy schedules, making their time together even more special.

“I don’t think so. I don’t think that has anything to do with it,” she responded. “I think you either really dig somebody, or you don’t. And I’m so blessed, we are so blessed that that happened for us.”

Plus, it doesn’t hurt that the Mad Men alum supports his reality star wife wholeheartedly, watching “every single” episode of RHOBH.

“Isn’t that cute, that Harry Hamlin even cares to sit and watch it?” gushed Rinna. “I mean, he really cares about seeing it. And now he’s totally into it. He has said to me, ‘You can’t help yourself. You just can’t help yourself.’ He said that numerous times. I’m like, ‘I know, I don’t know why. But you married me, so there you go.’ ”

Rinna and Hamlin tied the knot on March 29, 1997. They share two daughters, Amelia Gray Hamlin, 16, and Delilah Belle Hamlin, 19.