There was a cottage in the New Forest where, for a brief and bittersweet season, Dame Esther Rantzen was well enough to sit quietly and call her life bearable. She was 84, she had been diagnosed with stage-four lung cancer, and she had already paid her fees to Dignitas, the Swiss clinic where assisted dying is legal. The journey to Switzerland was, in theory, still open to her. And yet, because her pain had not yet crossed the threshold she had set for herself, she chose to wait — not fully understanding, as she has now made plain, that waiting would cost her everything.

Speaking publicly on Thursday, the 86-year-old broadcaster and Childline founder described the cruel arithmetic of her situation with devastating clarity. When she was physically strong enough to fly to Switzerland alone — a requirement of the Dignitas process — her suffering was not yet unbearable. By the time it became unbearable, her body could no longer make the journey. "Even though I had spent the money and made the plans," she said, she had not been ready, and could not have known that moment would be her last opportunity.

What she had feared most — pain witnessed by loved ones, indignity she cannot escape — is, she says, precisely what she is living through now. Her statement arrives on the eve of a renewed parliamentary vote on a bill that would legalise assisted dying in England and Wales for terminally ill adults with fewer than six months to live. The legislation, which has passed through several drafts and considerable scrutiny, has attracted fierce opposition, including from Paralympian Baroness Grey-Thompson, who warns that vulnerable and disabled people could face subtle but real pressure to choose death. Jersey has already legalised the practice for terminally ill adults, leaving England, Scotland, Wales and Northern Ireland united only in criminalising any assistance with dying.