UPDATE June 2, 2016:

A person of interest in Bethany Decker's disappearance has taken a plea deal.

Ronald Roldan, the last person to see pregnant Loudoun County mother Bethany Decker before she disappeared in 2011, has pleaded guilty in an attack on his girlfriend who was shot in the head, WTOP reports.

UPDATE Feb. 16, 2016: Person of interest in Decker disappearance could go free on technicality

Bethany Decker, a young military wife and mother, suddenly went missing in 2011 while her husband was deployed overseas.

Bethany Anne Decker was finally seeing the light at the end of a long road.

The 22-year-old was just a few credits shy of graduating from George Mason University with a degree in global environmental change. It seemed her studies by day and hard work as a waitress at night were about to pay off.

With Bethany away at college, at first it didn't worry her mother, Kim Nelson, that she hadn't communicated with her daughter in over three weeks.

But on February 19, 2011, Kim received a number of strange and foreboding phone calls. Some of Bethany's friends had noticed unusual posts on her Facebook page.

Kim's heart sank. She immediately called her own parents asking them to check on Bethany since they lived closer to her Ashburn, Virginia apartment.

"They drove there and they noticed that Bethany's car was parked crooked, had a flat tire, it was dusty, and they'd been by the week before and it wasn't like that, so they were really concerned," said Kim.

The unused car was a clue that something clearly wasn't right. A knock at her door soon proved that Bethany was nowhere to be found.

"That's when I said, 'Call the police,'" said Kim.

Investigators swarmed the complex, interviewing neighbors, friends and family. But three weeks had passed since Bethany had been seen. Only her car was left behind.

There were no signs of foul play or a physical altercation. Her bank cards had not been used and interviews with neighbors yielded nothing.

Bethany had literally disappeared -- without a trace.

For more information on the investigation,

Visit: Facebook - Help Find Bethany Littlejohn Decker

Discussion: Websleuths - Bethany Anne Decker