Margaret Bateman, 62, suffered from an agonising mystery condition which baffled medical specialists and remained undiagnosed. She spent the final three years of her life in terrible pain, bedridden and cared for by husband Michael.

Mr Bateman is now calling for a change in the law to allow people the right to die, saying he did what was morally correct.

The couple researched suicide techniques online and Mr Bateman made the agonising decision to help his beloved wife die using helium gas, just days before their 40th wedding anniversary.

The Crown Prosecution Service is now deciding whether to charge him – but after the opening of the inquest into his wife’s death he revealed his torment.

The tearful IT consultant, of Monk Ings, Birstall, told a reporter: “We were married for a few days short of 40 years. She was a brave and courageous woman who lived in agony for many years. She was healthy once and worked as an assistant in a care home. I had to give up work to look after Margaret full-time. The family were placed in an intolerable situation.”

He said they had even considered a trip to the Swiss clinic Dignitas, which has helped terminally ill people commit suicide, but were “prevented by circumstances”.

Mr Bateman, who has recently been diagnosed with spinal cancer, said: “Margaret was going to starve herself to death but she was threatened with being taken into hospital and force-fed.

“What I did for Margaret was morally right and correct. It’s what she wanted.

“It helped her out of her suffering. If society chooses to lock me up then society needs jolting around the issue of assisted suicide.”

He added that although he is currently on bail waiting to hear if he will be charged for aiding and abetting the suicide, he does not believe he will be re-arrested.

And he called for Dignitas-style clinics to open in the UK, saying: “Dignitas fulfils the needs of many people, that sort of facility should be available everywhere.

“What I did, logically, is no different to taking Margaret to Switzerland.

“I helped her to commit suicide. Nobody has been prosecuted for going to Switzerland.”

The Department of Public Prosecutions has issued guidelines which suggest that if someone acts out of compassion for a suffering loved one they are unlikely to be prosecuted – suggesting Mr Bateman will not face criminal charges.

The inquest heard how Mrs Bateman first considered suicide a year ago but changed her mind. However, on October 20 the couple made the decision to end her life.

They couple sent their adult son away from their home and Mr Bateman helped his wife commit suicide.

Assisted suicide campaigner Debbie Purdy said a framework was needed to allow people to die without help from relatives.

“I don’t think we should make friends and family the ones that carry out the final act, it is a horrible situation. There isn’t an easy answer, that’s why we need an open and honest discussion. ”