Morgan Banks, 18, subjected his long term girlfriend Sophie Smith, to a prolonged and brutal assault at a flat on Tempest Road, Beeston, Leeds Crown Court heard.
Banks, who had taken cannabis and cocaine, was also a regular user of the so-called ‘legal high’ spice, and had a paranoid belief Miss Smith was seeing other men.
Banks wept as the recorder of Leeds, Peter Collier, sentenced him to life.
The judge said: “This attack was without any justification or any real reason. You suspected her of having relationships with other men.”
Judge Collier said Banks beat false admissions out of Miss Smith and continued attacking her because of those admissions.
The judge added: “It was a savage and dreadful attack but I’m not able to be sure that you intended to kill her.”