This article originally appeared on The Guardian by Owen Bowcott on March 24th, 2017.

A woman says she has been left trapped in a “loveless and desperately unhappy” marriage after senior judges refused to allow her to divorce her husband of 40 years on the grounds of unreasonable behaviour.

The highly unusual ruling by the court of appeal triggered calls from divorce lawyers for parliament to introduce “no fault” divorce and warnings that the decision would force separating couples to make more aggressive allegations to justify marital breakdown.

Tini Owens, 66, who lives in Worcestershire, had applied to overturn a ruling by the family court that her marriage to her 78-year-old husband, Hugh, who is a retired mushroom farmer, had not broken down irretrievably despite her having an affair.

Her husband opposed her application, denying the allegations made against him. He told the hearing – held on Valentine’s Day – that he did not want to get divorced because they still had a “few years” left to enjoy.

One of the three appeal court judges, Lady Justice Hallett, said she had reached her conclusion “with no enthusiasm whatsoever”, adding: “It is for parliament to decide whether to amend [the law] and to introduce ‘no fault’ divorce on demand; it is not for the judges to usurp their function.”

The three appeal judges – Sir James Munby, the most senior family court judge in England and Wales, Hallett and Lady Justice Macur – dismissed Mrs Owens’s appeal in a ruling published on Friday.

Philip Marshall QC, representing Mrs Owens, said it was “extraordinarily unusual in modern times” for a judge to dismiss a divorce petition. The vast majority of divorces this century have been undefended.

“We cannot interfere with Judge Tolson’s decision [in the family court] and refuse the wife the decree of divorce she sought,” said Munby, who is president of the family division of the high court.

“Mr Marshall complains that the effect of Judge Tolson’s judgment is to leave the wife in a wretched predicament, feeling, as she put it in her witness statement, unloved, isolated and alone, and locked into a loveless and desperately unhappy marriage which, as the judge correctly found, has, in fact if not in law, irretrievably broken down.”

He added: “Parliament has decreed that it is not a ground for divorce that you find yourself in a wretchedly unhappy marriage, though some people may say it should be.”

Mrs Owens would be able to petition for divorce at a time when she could establish that she and her husband had been continuously separated for five years, Munby added.

The ruling prompted a chorus from divorce lawyers demanding that the law be changed.

Ayesha Vardag, one of the UK’s highest-paid divorce lawyers, said: “The question before the court of appeal was whether the judge was wrong to find that Mrs Owens’s petition was insufficient to support a divorce. The real question, whether it is right in 21st-century Britain to force couples through the Victorian farce of fault-based petitions, is one only parliament can answer.

“Fault-based divorce has caused significant misery and costs in this case. It does so on a smaller scale for thousands of couples each year. It is time that government stepped in and brought about meaningful reform to our outdated divorce laws.”

Prof Liz Trinder, a divorce law expert from the University of Exeter law school, said: “This decision is likely to have a deeply negative impact on people going through a divorce and on the family courts. It will mean couples will have to cite much more hostile examples of behaviour, whether or not that is based on reality. That will be a deeply regrettable backward step.

“Nearly half of all divorces are now based on behaviour. The reason for that is that the divorce can be achieved in a few months instead of having to wait at least two years. In practice, many ‘behaviour’ petitions have been based on very mild allegations. After Owens, that will change.”