Ellery Bennett, 47, of West Bloomfield was formally charged Friday with first-degree murder, The Detroit News reported. A judge ordered him held without bail.
Detective David Thompson of the West Bloomfield Police said Bennett came to a Royal Oak hospital Wednesday morning with what he said were accidental cuts. Thompson said Bennett appeared to have actually cut himself.
Bennett later told police his wife, Lisa, went for him with a butcher knife during an argument, and he stabbed her in self-defense, officials said.
In his note to his daughter, left at the house, Bennett apologized for the "choice" he had made.
"I tried to be the best dad for you but one thing I had no control over was your mother," he wrote.
Lisa Bennett filed for divorce last week. Bennett, who had recently tried to go into business online, was being sued for failing to repay loans.
He left other notes, including one for a neighbor and business associate, telling the man he was "number two on a short list of people I can't stand … and I got one."