Joe Hull, 18, and an accomplice stole Â£500 worth of items including irreplaceable jewellery after breaking into Vicky Wood's home on Cross Flatts Grove at Beeston, Leeds Crown Court heard.
Vicky Wood's mother and grandmother's wedding rings were stolen along with a television, a speaker, a digital camera and a safe, during the burglary on November 13.
Hull, of Oak Tree Drive, Gipton, admitted burglary and was sentenced to 32-months detention in a young offender institution.
Prosecutor, Louise Pryke, said Hull had previously been in a relationship with Vicky Wood's daughter.
Ms Pryke said: "She (Vicky Wood) took him in because he had nowhere to stay at the time and she fed him and washed his clothes."
The court heard the relationship between Hull and Vicky Wood's daughter later broke down and Hull no longer stayed at her home.
Ms Pryke said on November 13, after Vicky Wood left her home to go on holiday, Hull and another man broke in through a kitchen window.
Reading Vicky Wood's victim personal statement, Ms Pryke said she could not sleep and suffered from depression after the burglary, adding: "I fed him, I clothed him. What did he do with my mum's and nan's rings? Why did he do it? I treated him like a mum. Would he do this to his own mother?"
Hull, who has one previous conviction for three offences, admitted burglary.
Mitigating, Antony Farrel, said: "He was 17 at the time of the offence. He suffers from dyslexia. He is a man of very limited intellect."
Mr Farell added: "He is tremendously remorseful."
Sentecing Hull to 32-months in a young offender institution, Judge James Spencer QC, told him: "It was a very spiteful offence."