The bisexual actress, 23, who visited rehab three times and was jailed after being caught with cocaine, revealed she hit rock bottom and risked blowing her entire career via drug abuse.
"When my father was going public, that's when I hit rock bottom," Lohan told The Sun. "I tried to mask my problems with alcohol, cocaine and mind-altering substances. I ran myself down and lost track of who I was."
Referring to her May 2007 arrest for DUI (driving under the influence) and possession of cocaine, Lohan said: "I just thank God everyone was okay. But it was scary. I had three drinks, at most. I've been stupid and childish and I wasn't thinking."
The former child actress, who starred in The Parent Trap and Mean Girls, was ordered to attend alcohol education classes and insists she is now clean of her addictions.
"I've made some dreadful mistakes but learned from them - that has probably saved my life," she said.
"Mind-altering drugs are so dangerous. I'm allowed to drink now but I know my limits. Partying so hard isn't worth it."