A Gold Bar man's text messages to his new girlfriend on the day her ex-boyfriend was killed -- including one that allegedly read "it's done" -- helped lead to murder charges against both of them.

Brent T. Starr and Debra A. Canady were charged Monday with first-degree murder, Snohomish County deputy prosecutor Ed Stemler said.

The victim, identified by the sheriff's office as David Grimm, was stabbed three times in the back and beaten on the head June 26, apparently while he slept in the Sultan home he still shared with Canady.

Investigators say Canady and Starr had both wanted Grimm to move out, but he remained, causing tension in the new relationship between Canady, 46, and Starr, 30.

Canady and Starr both denied knowing who killed Grimm, 46, but they allegedly gave conflicting stories about communicating with each other on the morning of his death.

Canady told detectives she didn't talk to Starr that morning; Starr said he sent her text messages saying he loved her and asking how her day was going, according to court documents.

Detectives obtained the text messages from their cellular phone company and concluded that both were lying.