Thomas Wainwright was on the wrong side of the road and travelling at speeds of up to 95mph in his Maserati hire car, just minutes before the crash.
The 27-year-old ploughed into the Berlingo van driven by Theresa Wade, 29, on Mull in October 2015.
The court heard Wainwright had been drinking cider and whisky for eight and a half hours before the crash.
He will be sentenced next month.
During the trial Wainwright and his passenger,  42-year-old Jerome Lopez, had claimed that Miss Wade had been on the wrong side of the road and caused the accident but the jury did not believe them.
Witnesses from Mull told how Wainwright, who was with Mr Lopez, his mother's partner, had been drinking at a hotel, a pub and a distillery in Tobermory before having another two pints of cider in the Craignure Inn.
As he headed back towards Tobermory on the wrong side of the road his hire car smashed into the van driven by Miss Wade.
The court heard Wainwright was on Mull, along with members of his family, visiting his sick grandmother. He had flown into Edinburgh airport and hired the Maserati.
Prosecutor Tim Niven-Smith revealed that Wainwright, who worked as the first officer on the Â£6.26m yacht MY Mahogany based in the south of France, had a previous conviction for driving while unfit through drink or drugs.
At a court in Nice he was fined 700 euros and given a suspended sentence.
Judge John Morris remanded Wainwright in custody and banned him from driving.
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