The search warrants state relatives told police that 29-year-old Lauren Ashley-Nicole Phelps and 28-year-old Matthew Phelps were having money problems. Family members said Matthew was spending more money than the couple made and Lauren had recently taken "drastic" steps to limit her husband's spending.
In addition, text messages showed Lauren was "tired of arguing" with Matthew and "may be done with the relationship."
The documents also said that detectives learned from researching social media accounts that Matthew was "possibly fascinated with and mimicked a portrayed serial killer character from the movie American Psycho."
Matthew is charged with murder in Lauren's death.
The autopsy report showed the 29-year-old woman died from multiple stab wounds to her face, neck, torso, arms, and jugular vein.
In a 911 call, Matthew said he thought he killed his wife in a dream and woke up to find himself covered in blood and her dead on the floor.
"I have blood all over me and there's a bloody knife on the bed, and I think I did it," he said. "I can't believe this."
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He told police that he has trouble sleeping and may have taken too much cold medicine.
An empty package of Coricidin was seized during the initial search on Sept. 1, 2017.
At the time, Bayer, the makers of Coricidin, said in a statement: "Patient safety is our top priority, and we continually monitor adverse events regarding all of our products. There is no evidence to suggest that Coricidin is associated with violent behavior."