Dorothy Denny was fined £10,000 and given a 20 month suspended prison term at Gloucester Crown Court on Friday, May 19.
During the hearing, the judge, Recorder Neil Millard said he was ‘amazed that nobody was killed’.
The court heard that Denny had been drinking vodka at home for six hours on October 4 last year before getting into her Mini to drive to a garage to buy more alcohol around midnight.
Instead, she drove onto the exit road from the M5 at junction 8 and onto the motorway, heading south against the flow of traffic on the northbound carriageway.
Driving the other way was a woman from Birmingham who was suddenly confronted by Denny’s car coming towards her.
Prosecutor Nicholas Lee said “She was in lane three, travelling at the speed limit, when she was suddenly aware that a vehicle was heading towards her – head on – and she had less than a second to react.
“She managed to swerve a little but was still involved in a collision.
“The next thing she recalls is ‘still being alive’ in her vehicle, which was pinned against the central reservation.”
The victim, an athlete and personal trainer, was treated for broken bones in her wrist, whiplash injuries and bruising. Her injuries have had a major impact in her ability to work or take part in athletic events, the court was told.
Mr Lee said Denny, of Blenheim Drive, Bredon, Worcestershire, failed a roadside breath test and was taken to hospital with broken ribs.
Blood tests found she had 142 milligrams of alcohol in 100 millilitres of blood – the legal limit being 80 mgs.
In a police interview, Denny admitted drinking vodka for six hours.
She told officers she miscalculated the exit to get to the garage from a roundabout and entered the motorway.
Amber Morrell, defending, told the court that Denny was ‘extremely remorseful’ and was ‘mortified to find herself in this position.’
“She told the officer during her police interview that she has an alcohol problem and had gone to get more when she made her mistake,” said Ms Morrell.
“She offers her apologies to everybody involved.”
Denny pleaded guilty to causing serious injury by dangerous driving and causing a serious injury while intoxicated.
Denny was fined £10,000, given a 20-month prison term suspended for two years and banned from driving for 10 years.
She must attend 25 rehabilitation days and was given a four month alcohol treatment order.