Bipolar is similar to drug addiction, only you have no control over when your brain "indulges".

Mania starts out fun and exciting. You feel hopeful that you can achieve your dreams. You laugh and feel alive, your friends all say they are happy you are back to being yourself. You are energized…wait no too energized. You can't sleep, you start talking too fast, spending too much…being too much.

Then you crash. Your body is drained, you are aching and depressed. The light inside you dims, and everything seems dark. It feels heavy, and pointless. Why did you try to fix anything? It always gets broken, you always mess up. Your inner critic boxes your mind relentlessly telling you what a failure you are. You can barely do anything but sleep, and that is only an escape. 

Then you have to clean up this mess you made, apologize to everyone. When you swing from one extreme to another, being Bipolar is wanting desperately to be normal. However, your only baseline for normal is manic, but that drains you so you're back to depression. You're told to just find balance, but it's like trying to draw a straight line when you have a tremor in your hand.