Our moods always change. One minute we’re up, and the next, we’re down. Everyone’s like that. But sometimes the mood swings that everyone gets from time to time can go too far: someone can go from feeling giddy with joy to being unbearably sad, and back again. This can be a sign of mental illness, of bipolar disorder.
Bipolar disorder is a mood disorder where the person suffering from it swings back and forth, sometimes very rapidly or sometimes very slowly, between two very different moods or mental states, between depression and mania.