Mr Wright said Howlett had taken large amounts of crack cocaine in the hours leading up to the fatal crash on Denby Dale Road at around 6am on January 27, 2018.
He had been funding his habit by dealing drugs.
He had consumed a bottle of spirits but after he ran out of crack he had become more aggressive and had talked about ending his life.
While driving the BMW, a tyre came off and sparks were flying but he continued for a total of 20 miles.
During the drive he told a friend on the phone that he had already crashed twice and wanted to kill himself and that he intended to 'crash properly'.
Mr Wright told the court: "Kate would not have had any idea, in the dark, that a car was in her lane, not until the moment of impact."
After the crash, Howlett showed no concern for the other driver, but instead made attempts to get rid of drugs in the car and his phone.
Mrs Jaworski-Green, of Scissett, was cut free by firefighters but her injuries were not survivable.
Her father Paul paid an emotional tribute in a victim impact statement, which he bravely read out to a packed courtroom.
Mr Jaworski said his granddaughter Lydia, who was two at the time, continued to ask when her mummy was coming home.
"The loss of Lydia's mummy is heartbreaking," he said.
"We can see her thinking 'how come my mummy has left me?'
"Lydia said that when mummy has her car fixed she can come home. It appears that Lydia thinks that one day mummy will come home."
Mr Jaworski said he still felt guilt at having to take the decision to allow his daughter's life-support machine to be turned off, despite feeling that they hadn't properly said goodbye.
He added that his daughter's husband Chris still hadn't come to terms with his loss.
"October 4 would have been their sixth wedding anniversary," he added.
"We are all truly living a life sentence."
He said the death of his daughter was the 'cruelest thing that can happen in life'.
Mr Justice Butcher said Howlett, of Normanton, had taken the life of a complete stranger by his 'entirely selfish, inhumane and irresponsible actions'.
The judge described Mrs Jaworski-Green as an intelligent, ambitious and bubbly woman who felt intense joy in being a mother.
He added: "This is a terrible case of wasted life.
"You deliberately drove your car into a headlong collision with that of a complete stranger to you.
"You were intending to kill yourself. You killed her.
"She was innocently driving her Kia when you drove straight into her. She sustained appalling injuries and tragically died on January 29."
Howlett, who supported himself in the dock with crutches, suffered serious injuries in the crash.
The judge also disqualified him from driving for four years. Howlett will also be required to sit an extended driving test before he can regain a driving licence.