The Celebrity Big Brother winner was caught in a Range Rover in the early hours of January 28 after drinking on the train home from London to Newcastle.
After being pulled over by two police officers who witnessed her weaving down the road, a breath test revealed she was over double the legal limit, with 80 microgrammes of alcohol in 100 millilitres of breath, compared with the legal limit of 35.
She pleaded guilty to the charge at Newcastle Crown Court.
Defending Nick Freeman had told the court she decided to make the short journey from the railway station to her hotel despite originally planning to get a taxi.
He added: “She accepts that she is the author of her misfortune.”
The 25-year-old will now be unable to get a visa to travel to the USA.
Mr Freeman said she was close to landing a TV career in America but “that will not now happen as she will not get a visa”.
She will also pay a fine of £1,185.
He described Charlotte as “bitterly ashamed, contrite and embarrassed”.
“She would like to apologise to the court and her family,” he said.
“She would like to apologise to her legions of fans and supporters who she has let down in a huge way.”
Chairman of the bench Keith McIntosh said is “beggared belief” that she had been caught for a second time.
He adds: “We take drink-driving offences very seriously in this court, even more so when it’s not the first offence.”
In mitigation, Mr Freeman said “she contributes significantly back to society” and has a very “active and successful working life”.
He said she carries out work with charities such as Unicef and Barnardo’s and this conviction will have an impact on that.
Crosby, who won Celebrity Big Brother in 2013, has appeared in all 11 series of Geordie Shore.