Regrets

So people say that regret is not what you did do, but what you didn't do.
But aren't those two the same?

Example:

I regret that I didn't eat...
VS
I regret that I did chose not to eat.

Both mean the same thing, but one's affirmative, and the other negative...

SO they're synonymous... right?

SO regret is what what you did do, along with what you didn't do?

@___@ confused. This hit me while reading profiles.