This is fantastic! There is only one tiny change I would make. I think the last line needs to be broken into two so that last part really kicks your readers in the teeth. Let "you have done your best" sit on its own line and remove "and from the line before it:

and be satisfied that life is good.
You have done your best.

The period after good will give the reader that full pause, then you can punch them in the teeth with positive vibes.

Love it.