A Claygate woman who killed her husband after years of coercive and controlling abuse has been freed, bringing to an end 10 years of "hell".

Sally Challen, 65, bludgeoned 61-year-old Richard Challen to death with a hammer in August 2010, the Old Bailey was told.

The mother-of-two, also known as Georgina, had been jailed for life for the murder of the former car dealer following a trial at Guildford Crown Court in 2011.

But her conviction was quashed and a new trial ordered at the Court of Appeal in London in February, in light of new evidence about her mental state at the time.

Mrs Challen, of Claygate, Surrey, admitted manslaughter but pleaded not guilty to murdering her husband on August 14, 2010 and was due to face a fresh trial on July 1.

But at a hearing before Mr Justice Edis at the Old Bailey on Friday, the prosecution announced the Crown accepted her plea to the lesser charge on the grounds of diminished responsibility.

The senior judge sentenced her to nine years and four months in jail, time she has already served in custody.

Speaking outside court after the ruling, Mrs Challen said: "I just want to say how happy I am and want to thank my legal team and my family who have stood by me through all of this."

The judge said the killing came after "years of controlling, isolating and humiliating conduct" with the added provocation of her husband's "serial multiple infidelity".

He told her: "You felt trapped and manipulated because you were trapped and manipulated."

Mrs Challen appeared relieved and tearful in the courtroom packed with family and well wishers.

In a victim impact statement on behalf of her sons heard by the court, James Challen said the last 10 years had been "hell".

He said: "We have lost our father and we do not seek to justify our mother's actions."

"We believe the background circumstances are such that our mother does not deserve to be punished any further."

He said the family have conflicting feelings of "anger, grief, sadness and regret".

Prosecutor Caroline Carberry QC said the Crown's decision followed a psychiatric report which concluded Mrs Challen was suffering an "adjustment disorder" at the time.

Opening the facts of the case, Ms Carberry said Mrs Challens's relationship had hit the rocks after 31 years of marriage but they had attempted a reconciliation in 2010.

But suspecting he was seeing another woman, the defendant brought a hammer out of her handbag and attacked him from behind as he ate lunch at the kitchen table.

Afterwards, she went to throw herself off Beachy Head and told a chaplain: "I killed him with a hammer. I hit him lots of times... if I can't have him no one can."

When police arrived at the marital home they found the body of Mr Challen, with a hand written note on top reading: "I love you, Sally."

In her police interview, Mrs Challen said her husband was controlling but she still loved him, the court heard.

She also spoke about occasions when she believed he had been unfaithful to her.

In mitigation, Clare Wade QC told how Mr Challen was "domineering and controlling but not in a physical way" towards his wife, who worked at the Police Federation.

He made "humiliating comments about her weight" and Mrs Challen "put down and criticised at all turns".

On the day of the killing, it was Mr Challen's words "don't question me" that caused her to "flip" and hit him with the hammer, the court was told.