Lisa Rinna’s new Lifetime movie Mommy Meanest deals with a young woman receiving bullying, anonymous messages.

And as someone who’s in the public eye and active on social media, the former Real Housewives of Beverly Hills star, 60, can relate on many levels.

Asked how she navigates the often-hurtful comments that come her way, Rinna says it’s not easy, but her husband, L.A. Law star Harry Hamlin, 72, has some words of wisdom for her and their daughters, models Delilah, 25, and Amelia, 22.

“It’s very difficult,” she says in the new issue of PEOPLE. “Let’s just face it. Social media is a double-edged sword. And Harry, who is not on social media and has no connection to any of that world, always says to us — because he can see when we’ve seen something that is very unsavory and mean — he says, ‘What other people think of you is none of your business.’”

“So of course, we’ve tried to say that and teach that to the girls and you always have to go back to that,” continues Rinna.

Another of Hamlin’s sayings, according to Rinna: “What the eye doesn’t see, the heart doesn’t grieve.”

Taking her husband’s words to heart, though, is “easier said than done,” she says “because we see s-–– like this on a daily basis. There’s mean stuff out there constantly. And so I think it’s really tough for the girls and the kids, the teenagers growing up in this. It’s horrifying. It’s horrifying.”

Delilah, who has a supporting role in Mommy Meanest, says being raised by famous parents helped her prepare for what was coming as she entered show business in her own right.

“For me, and for Amelia as well, we kind of grew up in it,” she says to Rinna. “We saw things happening to you. But then when we got Instagram, we started having these types of comments and this negativity, and it’s been so long that I feel like we navigated it really well.”

“I just can’t imagine just being thrown into it and having to navigate it by yourself,” continues Delilah. “I’m so lucky I have my mom and my dad to teach [me and] give me these lessons like, ‘Don’t really care what other people think of you.’ But obviously, it’s still hard.”

In Mommy Meanest, Rinna plays Madelyn, a music teacher and mother whose daughter Mia (Briana Skye) receives hundreds of hateful text messages from unknown numbers. Mia eventually discovers to her shock and dismay that it’s her own mother sending the hateful content her way.

Rinna says she’s glad Delilah, who costars one of Mia’s classmates, didn’t play her daughter in the movie. “That would be, I think, too close to home at this point. That would actually have probably been really scary,” she says. “I’m not sure I could have done it with Delilah.”

Mommy Meanest premieres May 11 on Lifetime.