CHATTANOOGA, TN (WRCB) - As Jesse Mathews sits in the Hamilton County Jail, his girlfriend is left with a growing list of questions.
She invited Channel 3 inside her Chattanooga apartment home, but asked not to be identified.
"The Kevin that I knew was not Jesse Mathews," she said, "it was like a totally different person."
It wasn't until last Saturday that she heard the name Jesse Mathews.
She believed her boyfriend's name to be Kevin Moore. She thought he was a Colorado boy who served in the Army and loved guns.
"Looking back, there were things that should have raised red flags but they didn't because of the Army thing," she said, "like his enthusiasm for guns and the tattoo he had."
She was working at the Microtel on McCutcheon Road in early March when Mathews, and his parents, came in to rent a room. She says they told her they needed a place to stay while they looked for a home.
She and Jesse hit it off and in time she agreed to let him stay at her apartment until he found his own place.
He moved in with a collection of firearms and spent most of his time shopping for more.
She confirms what Channel 3 reported last week. She says Mathews purchased a rifle at a gun show in Chattanooga on March 27th from a vendor who did not ask for identification.
She says he told her he didn't have a driver's license because it was packed away when the family moved from Colorado.
"Never once did I ever question that he was going to use it for anything other than going to a shooting range," she said.
She says he also stocked up on ammunition.
"He made mention to me that it was armor piercing," she said thinking back to the day she visited the gun show with Mathews, "and he seemed kind of thrilled about it."
She says he insisted on visiting multiple pawn shops looking for a deal. Investigators say during that time Mathews was staking potential robbery targets out.
"Even the very U.S. Money Shop," she said, "we went in there twice."
The morning Mathews is accused of trying to rob the U.S. Money Shop on Brainerd Road she says he got up early and left without saying goodbye.
"He was carrying his rifle which was in a guitar case, and he grabbed my keys off the key hook in a way so they didn't jingle, he was being quiet," she said.
That was the last time she saw Mathews until his picture appeared on the local news.
She says she called Mathews to find out where he was. He told her he was picking up breakfast and spending time with family.
"I got off the phone with him at 9:41 and apparently all this happened at 10:30," she said.
She eventually reported her car stolen later that night, but says she didn't know Mathews was connected to Sergeant Tim Chapin's death until the TBI showed up at her door.
Police searched her home, questioned her, but found no evidence against her.
While she feels fooled, she says being in the dark may have saved her life.
"Being naive is kind of what kept me alive in all this," she said, "because at any point I could have been suspicious, figured out something, reported him to the police, been a threat, he could have done anything to me."
Mathews' girlfriend is not charged in this case and has cooperated fully with investigators.
As Channel 3 confirmed Wednesday, R.K. Shows, a traveling gun and knife show, is being investigated by the ATF on whether a vendor sold Mathews a firearm illegally.
Jesse Mathews is accused of shooting and killing Chattanooga Police Sergeant Tim Chapin following a botched robbery.
Mathews was shot by police. He was released from the hospital on Friday and booked at the Hamilton County Jail. His family is also facing charges for their connection to the crime.