The Real Housewives of Beverly Hills star feels protective of her former co-star, who recently lost her ex-husband to cancer and previously underwent months of personal turmoil.
Monty Brinson, who was married to Kim for three years in the '80s, passed away in January at age 58. The two are parents to daughter Brooke Brinson. Kim also has three children from other past relationships.
"I've texted her backwards and forwards and she's been very sweet," Vanderpump told E! News exclusively.
She said she and husband Ken Todd were invited to Brinson's memorial service but were unable to attend.
"She's so lovely and the problems that she's kind of had, it's been very difficult for her, I would imagine," Vanderpump told us. "But you know what, really, I hate? It's now if I see the show and I see people being negative about her, I hate that."
Kim, who is no longer a Real Housewives cast member, had last year battled substance abuse and legal issues and spent time in rehab.
Vanderpump told E! News she is "1,000 percent sure" Richards remains sober.
During her interview, Vanderpump also talked about her other Bravo reality show, Vanderpump Rules, which focuses on her West Hollywood restaurant, SUR. Stassi Schroeder, a former server, recently made her return on the show.
When asked if she would ever hire her back, Vanderpump told Bromley, "No. No! No."
She also said she did not regret paying money to stop a sex tape featuring Schroeder from being leaked.
"She's a young girl and she made a mistake and that was disgusting and that was an incredible breach of loyalty," Vanderpump said.
She also talked about bartender and Schroeder's ex, Jax Taylor, who made headlines last summer when he was arrested for allegedly stealing a pair of sunglasses from a store in Hawaii.
"I think he's learned a very, very valuable lesson," Vanderpump said. "I think it was tough on him."
The reality star signaled she isn't worried about employees stealing from her restaurants.
"We've got very tight security...if I was chasing every single person who's stolen half a bottle of wine behind the bar..." she said. "But all the money and that, no, no, no. I've got that figured out. I've had 29 restaurants."
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