As Christine Shopland, a mother of two, was being led from the crash scene by onlookers, Philip Carpenter, tapped her on the shoulder and fired at her with a sawn-off shotgun, Bristol Crown Court was told.
Mr Carpenter, 42, is said to have fired from less than 5ftaway and Miss Shopland's hip was shattered.
Mark Horton, for the prosecution, said that after Mr Carpenter fired he asked someone to get Miss Shopland a glass of water and then broke open the gun to disarm it.
Mr Carpenter, from Weston-super-Mare, denies attempting to murder Miss Shopland on 1 September last year and also denies possessing a shotgun with intent to endanger life. He has admitted causing grievous bodily harm, affray, possessing a weapon without a firearm certificate and driving while disqualified.
The court heard the couple had met when they were 15 and were together for 24 years before their stormy relationship ended. Mr Carpenter, who had an alcohol problem, became obsessive and watched Miss Shopland's movements almost daily. He traced her to her new job in the Rozel Hotel, Weston, Avon, where he regularly monitored her movements from a pub nearby.
He knew what was happening to him, said Mr Horton, as he was referred for psychiatric help when he told his doctor he was losing control.
Miss Shopland was kidnapped on the day Mr Carpenter saw her new boyfriend for the first time, the jury heard. Mr Carpenter saw him dropping her off near her work. That evening he persuaded her into his car and took her on a "tortuous" journey. He had his sawn-off shotgun across his lap and pointing towards her, the court heard. Mr Horton said Mr Carpenter told Miss Shopland: "I am going to take you somewhere and I will kill myself and you are going to watch."
At one stage, at traffic lights, she managed to leave the car, but he dragged her back, threatening nearby motorists with his gun. He continued driving very fast, swigging from a cider bottle, the jury heard.
But he lost control of the car on a bend beside the Castle and Comfort pub, near Wells, Somerset, and crashed. Pub customers helped the injured Miss Shopland from the car, but Mr Carpenter prevented them helping him until he recovered the gun, said Mr Horton. He said Mr Carpenter then followed Miss Shopland into the pub car park and shot her. He later told police he had sawn down the gun days earlier when he was "paralytic". He admitted being obsessed with Miss Shopland and told police he intended taking his own life.
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