IN her 20s, Sarah Levy looked like she had it all.
She was living in New York and had been taking full advantage of the night life there.
That also meant vodka martinis and taking part in 'Bachelor Mondays' with her friends - which included copious amounts of wine.
However, she said her 'fun loving' persona had just been hiding booze-related blackouts, along with anxiety and shame due to the amount of alcohol she was consuming.
Now in her 30s, she has been sober for five years after giving up booze at the age of 28.
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She said there were three key things that made her realise she had an issue with alcohol.
They were: blacking out when drunk, unpredictable behaviour and failed attempts to quit or scale back.
Writing in her book 'Drinking Games', Sarah said blackouts became her default setting throughout her 20s.
Her first experience was in high school, where she knocked back a cup of vodka to impress a crush, which resulted in her forgetting the rest of the night.
Blackouts can often happen when binge drinking and can occur when the alcohol in your blood rises fast.
Many people often don't remember what happened leading up to the blackouts, forgetting key details of an evening.
She said: "A switch would flip off in my brain, leaving my body to fend for itself alone in the dark."
Sarah, who now lives in Los Angeles, said her drinking habits and the consequences were unpredictable.
Sometimes the writer could have four glasses of wine and feel fine, and on other occasions one drink would leave her in tears, Insider reported.
"I wanted to believe I had control over the way my brain and body processed alcohol. But the truth was I never had any idea what would happen once I started to drink," she said.
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She recalled one instance where she had tried to impress her boss by drinking a lot at a dinner party.
But revealed that she had ended up in his friend's bed with a hazy recollection and a two-day hangover.
Sarah continued to drink despite social, work and physical issues arising.
Because of this, she started to try and control her consumption, limiting herself to a three drinks a night.
She also said she wouldn't drink on an empty stomach.
However, as soon as she had one drink and it 'hit her system' she said 'all bets were off'.
"Once I fully accepted that I simply couldn't drink safely, I felt an incredible amount of relief. I didn't have to work harder to be 'better' at drinking. I could just not drink," she said.
If you're struggling with booze, there are things you can do to get help.
Even if you can undertake everyday tasks while consuming high amounts of alcohol, this doesn't mean you are exempt and you could be a functioning alcoholic.
CEO of Delamere health and addiction specialist Martin Preston said those that suffer from alcoholism are exceptionally good at hiding their condition.
He said: "With few apparent negative consequences, a functioning alcoholic is unlikely to want to change whilst they feel they still have time.
"Alcohol addiction is at the chronic end of the spectrum of alcohol use disorders for which there is no cure.
"It can, however, be successfully treated and the sooner treatment is undertaken the better for the individual concerned and their loved ones."
