(UK) David Hoyle, of Idle Road in Bradford, hit Rebecca Bamber, 43, with wine bottles at her Widnes home in June then repeatedly stabbed her as she fled.
Chester Crown Court heard Hoyle left the scene calmly after the attack and smiled at a neighbour who was calling 999 while trying to help Ms Bamber.
Hoyle, 39, was given a life sentence and will serve at least 25 years.
Hoyle, who previously had a 15-year relationship with Ms Bamber, contacted her in May through the social networking site.
After they spent the night together at her Mersey Road home, he attacked her. The Crown Prosecution Service (CPS) said Ms Bamber's neighbour raised the alarm after hearing screams coming from her house. He saw the 43-year-old at her window, covered in blood and mouthing "phone the police". The neighbour called 999 and went to the back of her house, where he found Hoyle in the garden standing over Ms Bamber with a knife.
He rushed back to his own house to find something to defend himself with but, when he returned, Hoyle had gone. He then saw Hoyle drive away in his van, who then "chillingly" smiled at him, the CPS said.
The court was shown CCTV footage of the scene, which showed Hoyle leaving calmly while Ms Bamber's neighbour was on the phone to the emergency services. A recording of the 999 call was also played to the jury, in which the man can be heard trying to comfort Ms Bamber, saying: "It's all right Becky, I'm here, the police are on their way, it's all right darling, stay awake."
Police caught up with Hoyle near Runcorn Bridge, but he rammed their vehicles and escaped on to the M56, where he was again stopped before being Tasered. Following his arrest, Hoyle made no comment at interview. He pleaded guilty to manslaughter, but the CPS insisted he be tried for murder. Speaking after sentencing on Wednesday, prosecutor Richard Riley said Hoyle's claim that he had not meant to kill Ms Bamber was "ridiculous".
"Hoyle subjected Ms Bamber to a brutal and sustained attack and clearly intended to do her really serious harm. "She'd been stabbed 11 times with two different knives and three broken bottles."
He thanked the neighbour "for the courage he showed throughout this dreadful incident. His 999 call was the key to putting a very dangerous man behind bars," he said.
Det Insp Helen Spooner from Cheshire Police led the investigation. She said Hoyle had "shown no remorse". "We will probably never know the real reason behind Hoyle′s actions that day − only he knows why he subjected Rebecca to such a brutal attack in her own home," she added.
Ms Bamber's family issued a statement after the sentencing, saying: "We still find it difficult to believe that Rebecca has been taken from us in such a cruel and violent way. Not only has a mother been taken, but a sister and daughter too.
"It is difficult for us all to come to terms with what actually happened but, as a family, we hope that the conclusion of this court case will allow us some closure as we try to rebuild our lives and move forward."