A cleaner bit the nose and hand of a friend and neighbour during a drinking session.
Jean Collins had been friendly with her victim for several years although the relationship had been difficult at times, a court heard.
There was no explanation why Collins turned to violence other than she had been thinking about earlier tragedies in her family which had made her depressed.
Collins invited her friend to her flat in Ensign Court in Hartlepool, and the pair had a drink in the kitchen, prosecutor Emma Atkinson told Teesside Crown Court.
"As the victim went to leave the defendant came at her from behind," said Ms Atkinson.
"She grabbed her hair, pulling out clumps of it, and dragged her to the floor.
"The defendant bit the victim on the nose and ear, and as she was pushed away, bit her on the hand.
"The defendant described herself being covered in blood.
"She fled to a neighbour, and the police were called."
The victim suffered cuts and bruises, and the facial injuries required gluing, the court heard.
Collins, 55, of Speeding Drive, Hartlepool, admitted unlawful wounding on October 20.
She has 35 previous convictions including offences involving dishonesty and violence.
Ms Atkinson said Collins pleaded guilty on the basis she had been attacked, and had not bitten the victim's ear.
"The Crown do not accept that basis," added Ms Atkinson.
Martin Scarborough, defending, said in mitigation Collins had not been convicted of any offence since 2003.
"She is rehabilitated," added Mr Scarborough.
"Ms Collins did suffer minor injury in this incident, so we submit there was some provocation.
"She has since lost the flat, and will not be returning even were she's allowed to.
"She and her partner have secured a shared equity house which they hope will be a fresh start.
"Ms Collins works full-time as a cleaner, and she has caring responsibilities for grandchildren and her mother.
"There have been a number of tragic deaths in her family, it seems that all got on top of her.
"She is sorry and genuinely remorseful for how she behaved."
Judge Peter Armstrong sentenced Collins to 20 months in prison, suspended for two years, 120 hours of community work, and ordered her to pay £750 compensation to her victim at £50 a month.
The judge told Collins: "Your previous convictions were some time ago which means you had regained your good character.
"You had the good sense to plead guilty at an early stage.
"Bite injuries are always serious, but these injuries were not the most serious of their type when whole body parts are bitten off.
"I also have to be faithful to your basis of plea."
Collins was made the subject of an order banning her from contacting her victim, and banning her from visiting Ensign Court, both for two years.