For the past several months we've been witnessing the alarming breakdown of Amanda Bynes -- it's actually been happening over the course of several years, if you count her strange tweets and the announcement she was retiring and then unretiring from acting.

From the multiple car accidents, to bizarre behavior that includes locking herself in a dressing room and getting kicked out of a spinning class, Bynes appears to be spiraling out of control and possibly experiencing some mental health problems. The root of the 26-year-old actress's problems is unclear, but she's obviously not the first celebrity to deteriorate before our eyes.

These breakdowns can range from confusing to heartbreaking, but every year yet another celebrity seems to completely lose it.

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  • Tom Cruise

    Tom Cruise's 2005 breakdown began with the actor's<a href="http://www.metacafe.com/watch/28295/tom_cruise_freaking_out_on_oprah/"> appearance on "Oprah,"</a> where he jumped up and down on couches and declared his love for Katie Holmes. Then he followed that up by shocking the world in an interview with the "Today" show's Matt Lauer, in which he chastised Brooke Shields for using antidepressants to cope with her postpartum depression, Cruise labeled psychiatry a "pseudoscience" and he repeatedly told Lauer he was "glib" and didn't know the extensive history of psychiatry.

  • Bjork

    In 1996, Bjork and her son arrived at an airport in Thailand. An unsuspecting journalist greeted her with the phrase "Welcome to Bangkok" only to be met with the singer knocking her viciously to the ground and attacking her. Bjork blamed her rage on the fact that she had been hounded by the reporter and photographers for days.

  • Christian Bale

    in 2009, Christian Bale went nuts on the set of "Terminator Salvation" and verbally assaulted a member of the film crew for getting in his way.

  • David Hasselhoff

    David Hasselhoff's meltdown was made public for the world to see when his own daughter released a video that showed the shirtless "Baywatch" star lying on the floor drunkenly attempting to eat a cheeseburger. The actor later claimed that the videotape was deliberately leaked as part of a plan to make himself stop drinking, but no one believed that.

  • Mariah Carey

    In 2001, singer Mariah Carey made a <a href="http://newsroom.mtv.com/2011/07/19/mariah-carey-trl-10-years-meltdown-carson-daly/">bizarre appearance on "TRL"</a> where she showed up wearing nothing but a T-shirt, and later stripped down to her shorts and a tank top, handed out popsicles to the audience and made incoherent chatter: "All I know is I just want one day off when I can go swimming and look at rainbows and eat ice cream. And maybe like learn how to ride a bicycle." The singer was <a href="http://www.mtv.com/news/articles/1445424/mariah-carey-hospitalized.jhtml">hospitalized days later for "extreme exhaustion" </a>and a "physical and emotional breakdown," and she stayed under medical supervision for two weeks.

  • Anne Heche

    In 2000, actress Anne Heche had a very public meltdown shortly after breaking up with then-girlfriend Ellen Degeneres. Heche was found <a href="http://abcnews.go.com/Entertainment/story?id=116194&page=1">wandering in a rural area in Fresno, Calif.,</a> wearing nothing but shorts and a bra. She then rang a stranger's doorbell, and asked the homeowners about a gateway to outer space and if she could use their shower.

  • Charlie Sheen

    There have been many meltdowns and troubled times for Charlie Sheen, but the most recent stop on his train wreck began in January 2011, when he went on a bender in Las Vegas. After CBS failed to be able to reach him for his "Two and a Half Men" call time, he finally returned to his show late in the morning via private jet from Vegas. After spending all night partying and practicing similar behavior, Sheen was reportedly rushed to the hospital around 7 a.m. for severe abdominal pains. Sheen then went into a private rehab program and "Two and a Half Men" went into hiatus to give him time to recover. Sheen unloaded on other women he partied with in the days before he went into rehab, calling them "turds" and "losers." He also called "Two and a Half Men" creator Chuck Lorre a "clown" and made references to the fact that Lorre is Jewish. It continued like this for a while -- there was "winning" and "tiger blood" and so much more that we really don't want to remember.

  • Demi Lovato

    Things publicly took a turn for the worse for Demi Lovato in October 2010, when she underwent treatment for a "physical and emotional issue." The decision to head to rehab was prompted by a physical altercation with one of the Jonas Brothers' backup dancers, who told the Disney star's management about some of Lovato's dangerous behavior. After three months of treatment, Demi returned to the spotlight and opened up about her battles with bulimia and cutting, and being diagnosed as bipolar. Lovato has been extremely open about her issues, and admitted she was abusing drugs as a way to self-medicate. In an MTV documentary, the singer continued to share her struggle with fans and admitted she's still in process of recovery.

  • Britney Spears

    In 2007, Britney Spears entered a drug rehabilitation facility in Antigua, and stayed for less than a day. The next night, she shaved her head at a hair salon in Los Angeles and then <a href="http://www.spike.com/video-clips/ipu7zl/britney-spears-attacks-paparazzi-with-umbrella">attacked a photographer's car with an umbrella. </a> The singer entered herself into another treatment center weeks later and finished a monthlong program. After leaving Promises, she wrote on her website: "Recently, I was sent to a very humbling place called rehab. I truly hit rock bottom. Till this day I don't think that it was alcohol or depression. I was like a bad kid running around with ADD." In 2008, just days after losing a custody hearing, the <a href="http://www.nytimes.com/2008/01/05/arts/05brit.html?_r=0">singer locked herself in a room</a> with one of her children in her Los Angeles home and refused to hand him over to ex-husband Kevin Federline. Police were called to intervene and said the singer appeared to be "under the influence of an unknown substance." Spears was rushed to Cedars-Sinai Medical Center for evaluation and the following day a court suspended her visitation rights and Federline was given sole custody of their children. Three weeks later Spears was committed to the psychiatric ward of Ronald Reagan UCLA Medical Center and placed on a 5150 involuntary psychiatric hold. Later that year, a <a href="http://www.huffingtonpost.com/2008/10/28/britney-spears-dad-gets-p_n_138716.html">judge granted the singer's father a conservatorship</a> giving him control of Britney's finances and life decisions.

  • Mel Gibson

    Madman Mel has had a number of meltdowns over the years, but the horrible phone call with Oksana Grigorieva is definitely one of the worst. The actor reportedly left a seriously intense, profanity-laden voicemail message that shocked the world when he even threatened to kill the mother of his child and use her remains as manure.

  • Lindsay Lohan

    Let's just agree that everything Lindsay Lohan has done <a href="http://www.huffingtonpost.com/2012/06/24/lindsay-lohan-legal-timeline_n_1618579.html">since 2007 is part of one giant meltdown. </a>

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