Irish-born singer (and noted crazy person) Sinead O'Connor has cancelled the entirety of her upcoming tour. Calling herself "very unwell", she first took to Twitter to announce the cancellations, writing "Am going home and cancelling touring for the year. Doc had asked me not to tour but I thought was stronger than am."

O'Connor later released a statement to her official website:

"With enormous regret I must announce that I have to cancel all touring for the year as am very unwell due to bi polar disorder," the statement begins.

"As you all know I had a very serious breakdown between December and  March  and I had been advised by my doctor not to go on tour but didn't  want to 'fail' or let anyone down as the tour was already booked to  coincide with album release. So very stupidly I ignored his advice to my  great detriment, attempting to be stronger than I actually am. I apologise sincerely for any difficulties this may cause."

She added that she still hoped to be well enough to attend a tribute to Curtis Mayfield scheduled to be held at The Lincoln Center in July.

O'Connor has been in the midst of a public breakdown almost since the beginning of her career. In 1990, the press pounced on her after a well-publicized incident on Saturday Night Live in which the singer tore up a picture of the Pope while exhorting the crowd to "fight the real enemy."

In recent years she's given more than a few controversial interviews, at times declaring herself a lesbian, despite the fact that she's been married four times. During a 2007 interview with talk show host Oprah Winfrey, she revealed that she'd been diagnosed as bi-polar. She also revealed that she had attempted suicide on her 33rd birthday.

Her most recent marriage, to an Irish therapist named Barry Herridge who she met on the Internet, ended after just 17 days, though her Twitter account detailed a series of "lovemaking" sessions with the man.

"Yay!!! we decided to be boyfriend and girlfriend again an stay married but we did rush so we gonna return to b friend g friend," read one  recent Tweet.

As of press time, both her official website and Twitter account had been deactivated and were inaccessible.