What is significant about lady of shallot speaking at the end of the poem?

At the end of the poem, when Lady Shallot escapes in a boat, against the advise of the Arthurian legends, she forfeits her protective environment where she can remain pure and virgin like.  The very strict rules for women at that time were to keep them separated from others, especially the woem who were beautiful and of high position.  They were like a trophy or a prize whom was treasured and saved.

Upon leaving her protected tower, the Knights noticed her and commented on the strange occurence of her being in the boat by herself. Sir Lancelot comments on her beauty, but overall she is avoided because the Knights believe that no good can come of her escape.

She ends up dying which was already prophesized if she were to leave the tower.  However, her youth and her mind wanted more in a time when there was little available for women other than to be a posession of a Lord or Master.

In essence, she challenged the norm and paid the price with her life.  

we need to see the examples!

the two sonnets of sidney most closely follows the division between the octave and the sestet are the astrophel and stella sonnets.