Kim Kardashian runs a business empire worth millions – but has no one special by her side. Now 30 years old, the self-described "hopeless romantic" opens up in this week's issue of PEOPLE about the mistakes she won't make again, finding the right man, and her dreams of marriage and motherhood. "If you were to ask me in high school where I would be at 30, I would have said I'd be a housewife with four kids," she tells PEOPLE. "I've always thought real success is when you find a husband and make a home and raise an incredible family. That's what I was always looking for."

Things didn't quite work out that way. The reality TV star with the famous curves and the stiletto-sharp business savvy has achieved enormous success with workout DVDs, a credit card for teens, and a new autobiographical self-help guide, Kardashian Konfidential (coauthored with her sisters/co-stars of E!'s "Keeping Up With the Kardashians" – Kourtney, 31, and Khloe, 26). But Kim has yet to find someone to share it with. After her three-year relationship with New Orleans Saints star Reggie Bush, 25, ended last March – and a subsequent rebound romance with Dallas Cowboys wide receiver Miles Austin, 26, flamed out after just a few months – Kim Kardashian finds herself alone for nearly the first time in her adult life. "I'm so used to spending a lot of my energy on a relationship and having to make it work," she says. "It makes me feel more powerful being on my own." Now she's willing to wait for Mr. Right. "I might have thought that love was the one thing missing is my life before. I don't think that anymore."

It's a dramatic role reversal for Kim, long regarded as the maternal one of the bunch. But while Kourtney became a mom to son Mason, 11 months, and Khloe wed LA Lakers star Lamar Odom last year after a whirlwind courtship, Kim has gone from seemingly ready-to-wed to suddenly solo. "Is it weird that I'm now the single one? It's definitely a change for me," she admits. "I have always been the one in a relationship. I like that role; I want that best friend partnership. I love taking care of my guy, I love cooking, I love shopping and getting him little presents."

But the woman whose candid confessions on dating, dieting, and her admitted OCD streak have endeared her to fans – including her 5 million Twitter followers – readily acknowledges that her love life has often lacked stability. (Eager to settle down just out of high school, she eloped with music producer Damon Thomas at age 19; they split four years later). She cites the glare of the reality TV cameras as a factor in her August breakup with Austin. "Had we gotten to know each other when we weren't filming, it would have been easier," she says. Combined with tabloid attention, "he was thrust into a world that he didn't really want to be in," she says. "I don't blame him or anyone. Unless you're used to it, you don't know what to expect."

In fact, Kim says that her hectic schedule could prove a permanent stumbling block for all but the most dauntless suitors. "I think it's intimidating, I really do," she says of her work ethic. "…And I also want to know: Does this person want to date me only because I'm on a reality show? And they want to be on it? You don't want that kind of person." But for the right guy, Kim would be willing to put her career on a back burner – a bit. "Whatever relationship I'll be in next, I realize I can't be this work machine all the time. It's not realiztic. I want a normal relationship."

Most significantly, she says she has loosened her once-rigid romantic checklist. "I want to fall in love, but I'm not desperately looking for it." Yes, she still wants to settle down and raise four kids – but she's no longer in a rush. "Give me a few years before that happens," she tells PEOPLE. "A guy isn't the only thing that will make me happy. If I never find romance or love, that will be okay. It's what I want – but it doesn't define me."