I think you've got it mostly right. Here's how I hear it. Not 100% confident in the "awful low" and "grandest" lines, unfortunately. Definitely sounds kinda like she said "grabbest" or grabbiest as you suggested in the other questionable line, but I have to assume she meant grandest, unless there's a slang term I'm not familiar with.

ADAM'S RIB
(Ian Campbell - as sung by Lorna Campbell)

She's lying in a meadow fair,
And youth is singing in her blood.
With daisies flaring in her hair,
She's listening to the stars that wheel above.

She hears the thunder of the moon
Commanding tides that, late or soon,
Will let her know its lunatic demands.

She weeps a tear she doesn't understand,
While smiling at the eager heart,
So keen to play the traitor's part.
And to wrap her into love.

Oh, God, it was a cruel trick to play,
To keep the stone and throw the fruit away.
You made him whole but cast me from a part
He lost a rib, but I gave up a heart.

She's sitting in a dim saloon,
The glowing ember in her face
Betrays her presence in the gloom.
She's looking awful low and feeling blue,

And red as blood, the fingertips,
That raise the pink gin to her lips,
And tint with rose the grandest memories.

She feeds a chocolate to her Pekingese,
And smiles a smile to tear the soul,
A painted mask to hide the hole
Of nothing left to do.