What Happened to Tanya and Jay?

Tanya's body was found at the bottom of a ditch in rural Skagit County, some 80 miles north of Seattle. She wasn't wearing any pants or panties and her bra was pushed up over a breast. Tanya had been shot in the head at close range. It was a quick execution. Such a crushing feeling that all of a sudden you see her lying there. How did this happen? Why did it happen?