In Act 1 why does lady Macbeth ask the spirits to "unsex" her?

Lady Macbeth asks them to do this (or wishes they could)
because she wants to help her husband kill Duncan and do the other things that he needs
to do in order to become king.  Her request is based on the idea that women, by their
nature, are unsuited for doing brutal things like
that.

Lady Macbeth is worried that her husband lacks the
guts and the drive to do what is necessary to take power.  She thinks she has them, but
she would need to stop being a woman in order to act on her
impulses.

As a woman, she is too likely to feel guilt and
remorse, she says.  So she wants to be filled with cruelty like a
man.

readability="12.887417218543">

Come, you spirits
That
tend on mortal thoughts, unsex href="../../../../../macbeth-text/act-i-scene-v#prestwick-gloss-1-5-129">me
here
And fill me, from the crown to the toe, top-full
Of direst
cruelty! Make thick my blood,
Stop up the access and passage to remorse,(45)

That no href="../../../../../macbeth-text/act-i-scene-v#prestwick-vocab-1-5-7">compunctious
visitings of href="../../../../../macbeth-text/act-i-scene-v#prestwick-gloss-1-5-130">nature

Shake my href="../../../../../macbeth-text/act-i-scene-v#prestwick-gloss-1-5-131">fell
purpose nor keep peace between
The effect and it!