IMAGINE feeling on top of the world one day - and at the bottom of the barrel the next. For people who suffer from bipolar disorder, this is their reality. Catherine Zeta-Jones representative made a surprise announcement Thursday that she had checked herself into a mental health facility for five days to treat her bipolar disorder, but a member of Fox News Medical A-Team says the actress likely has been dealing with the disorder most of her life. The 41-year-old Academy Award winner has been under a great deal of stress in the past year: Her husband, actor Michael Douglas, 66, was treated for cancer and her stepson, Cameron, is serving a prison sentence. On top of all that, Zeta-Jones is always in the public eye, as she and Douglas try to raise their young children, Dylan, 10, and Carys, 7. Zeta-Jones has seemed to handle that stress with ease - shes been the devoted wife and mother, gracing the red carpets with style, not a hair out of place. So her announcement may leave many wondering how someone in the spotlight can suffer from such a crippling mental disorder without letting the public see the signs. It shouldnt be surprising to anyone that a successful, beautiful woman would come to suffer with bipolar II disorder, said Dr. Keith Ablow, a psychiatrist. Success and beauty dont insolate anyone from psychiatric disorders. Zeta-Jones rep said in a statement that the actress made the decision to enter treatment following her husbands very public battle with throat cancer. Stresses in life - like dealing with kids, or a spouses illness - can certainly fuel the roller coaster from low to high, Ablow said. But many people go through awful struggles and are not bipolar - and vice versa. Fox News