"I had to make a commitment to myself to be alone: no flirting. No possibility of anything. No boys in any way, shape or form. I said, 'I'm shutting it down,' " the star – who produced and stars in the steamy thriller The Boy Next Door (out Friday) – tells PEOPLE in this week's cover story. "I'd never been alone."
In a revealing interview at her sprawling home in Los Angeles, the superstar and refreshingly hands-on mother, to 6-year-old twins, Emme and Max, shares what was a sometimes-lonely journey of self-discovery.
"I always found my comfort in another person," says Lopez, whose divorce from singer Marc Anthony was finalized in June, 2014, three years after their split. "Instead of giving myself time to heal and be on my own, I was so afraid to be that I was always like, 'Okay somebody else just come in here and help me forget I'm in so much pain.' "
Newly empowered after facing her ultimate fear – "I was terrified of being alone" – Lopez is upbeat about the future. "Listen, at the end of the day, love is the best thing," she says. "But what I've discovered is that I can't get that from somebody else. It's the love inside me, for myself, that will help me through."
Currently single, the hard-working star, 45, hasn't sworn off romance for good.
"I still believe in the fairy tale," she says. "The more I work on myself, the more I give myself the opportunity to share a really deep and meaningful relationship that can give me my fairy tale and last forever."
These days, Lopez is "open" to dating but vows to take things slowly.
"I'm not rushing into anything in any way, shape or form," she says. "And I'm not looking."
For more of this exclusive interview, and to see inside Lopez's amazing L.A. home, pick up the latest issue of PEOPLE, on newsstands Friday