Why the sigh, Robert?

I just finished reading your reflections on Robert Frost's poem The Road Not Taken. It seems there is some controversy about the meaning of the poem. Many of you believe that Frost chose the grassy road, the one less traveled. Others of you explained that Frost wished he had taken the grassy road, but actually took the other road and that is why he gave a sigh. Read Frost's poem one more time. Then, respond to this post and tell me what you think Frost really meant. Use examples from the poem to support your opinion.

The Road Not Taken
by Robert Frost (1874-1963)

Two roads diverged in a yellow wood,
And sorry I could not travel both
And be one traveler, long I stood
And looked down one as far as I could
To where it bent in the undergrowth;

Then took the other, as just as fair,
And having perhaps the better claim,
Because it was grassy and wanted wear;
Though as for that the passing there
Had worn them really about the same,

And both that morning equally lay
In leaves no step had trodden black.
Oh, I kept the first for another day!
Yet knowing how way leads on to way,
I doubted if I should ever come back.

I shall be telling this with a sigh
Somewhere ages and ages hence:
Two roads diverged in a wood, and I—
I took the one less traveled by,
And that has made all the difference.