Minutes later, her two sons Sheldon, 22, and Slade, 19, arrived home from a party. They saw their step-dad getting arrested, his pyjamas covered in blood.
The court was told the couple downed three bottles of Prosecco between them in the hours before Melanie's death.
When police arrived, they found Clark had tried to kill himself with gas and then he begged officers to kill him.
"Melanie Clark had told her husband she wanted him to leave their home," prosecutor Benjamin Aina QC, according to The Sun.
"He couldn't take the rejection and killed his wife. They had been married for 10 years. They had no children together, but she was the mother of two boys and two girls from previous relationships."
The court heard that Melanie had told friends in November she was "not happy".
"The master bedroom of the house is the bedroom where Melanie slept. This is where the body was found," the prosecutor added.
"There was a knife that had been found near the body. It was about 10 minutes before midnight that David Clark telephoned the emergency services.
The prosecutor continued: "He says to emergency operator: 'I'm sorry, I've killed my wife. My wife started being s*** again.
"I'm totally in love with my wife. She f***ing killed me and I had to stop her. I can't believe I f***ing did it.
