A woman who stabbed her son to death after a mental breakdown brought on by her bullying boyfriend has described him as a “controlling monster”.

Peter Chilvers, an airline pilot from Northwich in Cheshire, was jailed for 18 months after he was convicted of controlling and coercive behaviour against Magda Lesicka, who he met when they worked at Ryanair.

Lesicka, Polish national, was jailed for 15 years in July for stabbing to death their 23-month-old son, James, at her home in Wythenshawe, Greater Manchester, in August 2017.

Her sentencing hearing was told Chilvers had subjected her to relentless psychological torment during their relationship.

The couple had been together since 2010 but Chilvers cheated on Lesicka from 2014 with another Ryanair cabin crew member, Lisa Spencer, who is now his partner and mother to his two young daughters.

Chilvers had repeatedly threatened to kill Lesicka if she removed their son from his care and demanded they continue to live together at a new home he bought in the Cheshire village of Wincham.

Lesicka admitted manslaughter by reason of diminished responsibility on the basis her mental illness emerged without warning and she had no memory of committing the offence.

She went on to give evidence in the prosecution of Chilvers at Manchester crown court, and parts of her victim personal statement composed in prison were read out at his sentencing.

The former flight attendant said the statement was “a closing chapter on the most horrific experience I have ever had, and now I only have my flawed memory to work out how it got to this point.

“It’s hard to see myself as a victim given the tragic outcome. I know my life has been changed forever and there is nothing I can do change it back. I have the rest of my life to contemplate these events and it is a daunting prospect.

“When I started a relationship with Peter Chilvers I had absolutely no idea he would be the controlling monster I discovered him to be. It is important that the public understand what Peter Chilvers’ abuse did to me. It destroyed me. I have no idea how he achieved this and I will probably spend the rest of my life trying to work out how he turned the confident ambitious me into what I am now.”

She went on: “I have very little left in my life, not even my freedom. This is my burden to carry. I accept it in the hope that some day I can move forward. I was broken by him and I can never be the person I was before I met him. I am alone now, I feel ugly, worthless, defenceless, ashamed, guilty and weak.

“Peter was responsible for doing what he did to me. I am genuinely terrified he will do this to someone else.”

His controlling or coercive behaviour between December 2015 and August 2017 included using or threatening physical violence, forcing her into degrading sexual acts and isolating her from her friends.

Chilvers, of Hewitt Grove, who has no previous convictions or cautions, was cleared last month by the jury of two allegations of rape and one count of assault by penetration.

Reporting restrictions on the case were lifted as the court heard that Lesicka had “unequivocally” waived her anonymity as a sexual offence complainant in her victim personal statement.

Sentencing, Judge Patrick Field QC said he was satisfied that part of Chilvers’ controlling behaviour was sexual.

He told him: “While I accept that the jury acquitted you of the more serious sexual offences, it is undoubtedly the case that throughout the relevant period, particularly when you and Magdalena Lesicka were not sharing a bed, you continued to treat her as your sexual property.

“To use her words, you would help yourself to her body and she would consent because she felt that she had to do whatever was required of her. Such was your control that she felt she had to put up with it.

“Throughout the period with which this indictment is concerned, your behaviour towards Magdalena Lesicka was that of a selfish, entitled bully. I have detected no more than a hint of your remorse.”

Mark Ford QC, defending, said character references for Chilvers provided to the court painted a “very different picture” to that given by Lesicka.

He said Spencer had attested to a supportive, cooperative and loving relationship with Chilvers.

Ford said Chilvers was the sole carer for their daughters while Spencer was at work and that immediate custody would be a “significant threat” to his mental health.

Arguing for a suspended sentence, he said: “In short, he is a man on the edge. Just a few years ago, Peter Chilvers had the world at his feet. Now he faces the difficult and, if I may say so, painful challenge of rebuilding his life.”

Outside court, DCI Richard Eales, of Greater Manchester police, said: “If people take anything away from this heartbreaking case, please let it be that there is support and help available for those who are suffering at the hands of domestic abuse.

“Most importantly though, I hope today’s result has seen justice served for the person who matters most: James.”