Debra was last seen in Weymouth, Massachusetts between approximately 3:00 and 4:00 p.m. on June 20, 2000. Her husband, Luis Melo, claims they got into an argument while he was driving and she demanded to be let out of the car Route 18, south of the former South Weymouth Naval Air Station. She has never been heard from again. Luis says he drove a couple of miles down the road, then came back about twenty minutes later to the site where he dropped her off, but Debra was gone.

Luis did not report Debra missing for one to three days (accounts differ). Her family says they had a troubled relationship and Debra had gotten an emergency restraining order against him in 1996, stating in court documents that Luis had threatened to harm himself or her or both of them if she tried to leave him. The order was lifted after only two weeks, however. Debra and Luis had been married for fourteen years by 2000, and she was reportedly considering divorce at the time of her disappearance.

Luis failed a lie detector test about Debra's disappearance. Police have not called him a suspect in Debra's case, but they have publicly wondered why he does not take a more active role in looking for her. Luis has not participated in any searches for Debra. Investigators state that his behavior and attitude is not consistent with that of a grieving husband. He has not been charged in connection with her case, however, and police could not find any evidence as to her fate in his car. Luis maintains his innocence in Debra's disappearance and stated he believed she was still alive. He was later convicted of assaulting his girlfriend and sentenced to probation. He has since remarried.

Debra's family states that she was a devoted mother and it would be uncharacteristic for her for willingly abandon her two children. They believe she is deceased. Debra and Luis managed a Dunkin' Donuts restaurant in Braintee, Massachusetts in 2000. Her disappearance is considered suspicious and her case remains unsolved.