Amanda Bynes seems ready to move on from her troubled past.

In a new interview with Paper Magazine, Bynes opened up about her public downward spiral, including her infamous tweets directed at family members and other celebrities, and how life has been since getting sober almost four years ago.

Bynes said despite her "good girl" image when she was younger, she started smoking marijuana at 16 and that eventually escalated to her using harder drugs like molly and ecstasy. She said she also started using Adderall on a regular basis after "faking the symptoms of ADD" so a psychiatrist could write her a prescription.

The 32-year-old fashion student said she thinks her use of Adderall played a major role in her public downfall, which the world first got a glimpse of in 2010 while she was filming the movie "Hall Pass."

"When I was doing 'Hall Pass', I remember being in the trailer and I used to chew the Adderall tablets because I thought they made me (more) high (that way)," she told the magazine. "I remember chewing on a bunch of them and literally being scatterbrained and not being able to focus on my lines or memorize them for that matter."

#BreakTheInternet: @amandabynes. Having spent years out of the spotlight, Bynes steps back in and opens up about her tumultuous — and remarkable — journey. https://t.co/NFpW1Yy7AN pic.twitter.com/w9TXCtwB6n — PAPER Magazine (@papermagazine) November 26, 2018

Bynes eventually quit "Hall Pass" and then made an impromptu announcement on Twitter that she was retiring from acting. She said her sudden desire to leave acting was due to her being high all the time and criticizing the way she looked on film during a screening of her 2010 movie "Easy A."

"I literally couldn't stand my appearance in that movie and I didn't like my performance. I was absolutely convinced I needed to stop acting after seeing it," she said. "I was high on marijuana when I saw that but for some reason it really started to affect me."

Suddenly out of work, Bynes said her drug use increased.

"I just had no purpose in life. I'd been working my whole life and (now) I was doing nothing," she told the magazine.

She added: "I got really into my drug usage and it became a really dark, sad world for me."

Bynes said she is "'really ashamed and embarrassed" by what she did during that time, telling Paper Magazine that there are still some things — like the tweets — that she doesn't like to talk about.

"I can't turn back time but if I could, I would. And I'm so sorry to whoever I hurt and whoever I lied about because it truly eats away at me," she said. "It makes me feel so horrible and sick to my stomach and sad. Everything I worked my whole life to achieve, I kind of ruined it all through Twitter."

Now, Bynes is focusing on other things. The former child star is getting ready to graduate with her Associate of Arts degree in Merchandise Product Development from Fashion Institute of Design and Merchandising in Los Angeles and hopes to one day return to acting.

"I have no fear of the future," she said. "I've been through the worst and came out the other end and survived it so I just feel like it's only up from here."