“go cold turkey” = suddenly stop doing something that is usually a bad habit.
“Phil tried to go cold turkey on his drinking addiction, but he couldn’t stay away from stuff.”

“drink like a fish” = drink alcohol excessively
“She tends to drink like a fish when she gets together with her friends.”

“drown one’s sorrows” = drink to stop your unhappiness
“Trying to drown your sorrows in a bottle of whiskey won’t solve your financial problems.”