"I figured, if I share my experiences with my friends, family and loved ones then maybe I can help inspire those who are currently facing the same difficulties that I was to make a change."
Wellington television producer Lotta Dann, who founded support website Living Sober after writing a book about her own struggles with drinking, said Ms Williams' letter was courageous for someone so young.
"There are loads of New Zealanders who are personally struggling. Through me going public and now people like Anna, that's fantastic; the more people that are brave enough to say they have struggled with alcohol, the more people who are in their own private battles can say they are not alone."
Mrs Dann, a mother of three and wife of political journalist Corin Dann, said the site had attracted 1,600 members in just six months, and had been visited by hundreds of thousands more.
"It's like this great taboo, that you can't say, 'I struggle with alcohol', but there are thousands of others having their own struggles and battles."
She said there was a fallacy in New Zealand culture that life was less without alcohol, and she feared she would not be able to unwind, socialise or bond with friends and colleagues without drinking.
"It is such an amazing feeling - you can have fun and learn to relax and all of those things without booze."
National Committee on Addiction Treatment chairwoman Vanessa Caldwell said she praised Ms Williams' efforts and hoped other Kiwis would be inspired to address any of their own concerns. "Anything that inspires people to make changes when they might be concerned about their drinking is positive."
Mrs Caldwell said if people were worried about the toll alcohol was taking on their lives, they should consider making changes.
"Things like blackouts, forgetting what you did the night before, finding out the next day you have done things, spending a lot more money than you planned or drinking a lot more than you planned, starting to drink on your own ... they are all possible signs you are starting to verge on an unhealthy way [of drinking]."
Mrs Caldwell said an alcohol-free initiative called Feb Fast was encouraging people to give up alcohol for the month.
Where to get help
• Alcohol Drug Helpline on 0800 787 797 (10am-10pm)
• LifeLine 0800 543 354 (24 hours)
• Living Sober support network
• Alcoholics Anonymous