On May 24, Michelle Addington, who described herself as Lockhart's best friend since elementary school, told police Lockhart had failed to show up at her child's confirmation May 22 and a party before the confirmation.
"Nothing but death would have kept her from these events," Addington said.
Police found her body less than a minute after starting the search, according to the reports.
He also pleaded guilty to one count of interfering with electronic communications for cutting a neighbor's phone, internet and air conditioning lines.
He said he couldn't tell if any of Theresa's medication or clothing was missing, and eventually told police he would have to consult with his attorney before answering any more questions.
Police checked several area hospitals with psychiatric units to see if Lockhart had checked in.
Killing wife was 'senseless act,' Lockhart says in suicide note Theresa Lockhart's disappearance set off a months-long manhunt for any clue of her.
Meanwhile, Lockhart denied knowing anything about her disappearance, refused to cooperate with police and was arrested four times for several offenses.