Niki Lopez once had a disturbing nightmare, and it still haunts her. In the dream, she is panicking about finding the perfect outfit for her young son to wear before she introduces him to Dwight “Malachi” York — the cult leader who repeatedly sexually abused her decades before when she was a child. Lopez began being abused by York when she was 13 after her family moved into his compound when she was 11. “When kids visited him they were in their best outfits,” Lopez, now 43, tells PEOPLE about the leader of the United Nuwaubian Nation of Moors, a black supremacist cult she finally escaped in 2000 at the age of 25. The cult is featured in next Monday’s episode of People Magazine Investigates: Cults, airing July 9 (9 p.m.