How can I go from being happy moments ago right into wanting to lay down on the subway tracks to die not long after?

@HootyTheNightOwl Most likely, I do suffer from it.

@Astro If you hit the floor so quickly, then depression or bipolar disorder would be my two usual suspects.

i hope you feel happier soon.

@HootyTheNightOwl It comes in cycles I should be swinging back up before the night ends. My mood constantly changes without warning.

@Astro i suspect that mine is misdiagnosed bipolar type 2... i spend most of my time feeling depressed and prozac didn't really change matters any for me.