The reality star has had a tense relationship with her sister and former RHOBH costar

By Aili Nahas
Updated March 23, 2016 03:00 PM
Credit: Jason Merritt/Getty

After a painful – and public – feud, including a nearly yearlong estrangement, Kim Richards is picking up the pieces of her relationship with her sister Kyle.

“I miss my sister,” Kim, who stars on Lifetime’s The Mother/Daughter Experiment: Celebrity Edition, tells PEOPLE exclusively in this week’s issue. “I look at her face today and I want this relationship.”

The siblings, who were both successful child actresses, became costars on The Real Housewives of Beverly Hills in 2010. The first season’s unforgettable finale culminated with Kim and Kyle’s bitter fight in the back of a limousine, in which Kyle outed her sister as an alcoholic. Their relationship stayed fraught with tension over the next few years; the pair were even estranged for nearly a year in 2014.

“It was very hard,” says Kim, 51. “I had a lot of hurt and disappointment. I needed to heal and find a way to move forward.”

RELATED VIDEO: Does Kyle Richards Blame The Real Housewives of Beverly Hills for Her Roller Coaster Relationship with Sister, Kim?

For exclusive photos and much more from Kim Richards, pick up the new issue of PEOPLE, on newsstands Friday

In order to do that, Kim says she had to leave some of the past behind. “Sometimes when you unravel things from the past, it just gets worse,” says Kim. “If there is anything boiling, that needs to be talked about 100 percent. But if there are things that are just unsettled, leave them there. There are certain things better left behind.”

And despite the fighting, “It never meant that I didn’t love her and it never meant that I didn’t miss her,” says Kim. Now, “I’ve let it go. And I’m happy with our relationship again.”

The Mother/Daughter Experiment airs Fridays (10 p.m. ET) on Lifetime.