The troubled 'Nothing Compares 2 U' singer sought help for “thirty years of being a weed head” and is proud she has now kicked her addiction to marijuana.
Sinead plans to spend the next 12 months getting extra support in her recovery by staying at a sober living facility.
She shared: “I was in rehab by the way. For thirty years of being a weed head. Can proudly state I now have clean p**s and will be in a 'sober living environment' for the next year.
“It's more like a home environment. Only its complete with support system. Which is a first for me. Proud of self. Wasn't easy.
“0-18 years in Ireland and then 34 years in music business and the s**t that's gone on for the last year.... it's a miracle I wasn't on every drug in sundry. #CleanP**sRocks (sic)”
The 49-year-old singer - who has been suffering with gynaecological problems for three years and had a hysterectomy last year - also revealed she has undergone hormone replacement therapy but has been left in agony after her liver was accidentally “cut” during the operation.
She wrote on Facebook on Saturday (22.10.16): “Still feeling so miserable from surgery. I don't recommend it Lost awful lot of blood as liver got cut accidentally so am weak as F**k.
“But I do recommend hormone replacement. Am Different person. Stupid Irish doctors never recommended it to me all year but I finally got it two weeks ago in US and am me again. Thank you to doctor here in America. And thank you to my surgeon.(sic)”
And she added on Sunday (23.10.16): “F**k. Gotta go to emergency. Liver all f***ed and killing me. Can't breathe properly it so sore. Am posting as am lonely. Story of life...”
Bang Showbiz