What details show that Lady Macbeth is feeling isolated and anxious in Macbeth?

In Act 5 of Macbeth, Lady Macbeth
certainly shows that she feels alone and isolated and is now suffering mentally from the
acts that her husband has performed behind her back.  Lady Macbeth cannot believe that
Macbeth has gone so far as to murder Lady Macduff and her children, and this event is
one that pushes Lady Macbeth over the edge.  She says, "Yet who would have thought the
old man to have had so much blood in him" (V.i.37-38) when she thinks about all the ill
deeds that Macbeth has done. 

In addition to this, Lady
Macbeth also shows that she is feeling isolated and anxious earlier in the play when she
covers up for Macbeth at the banquet.  When Macbeth made the plans with the murderers,
he left his wife out of the scheme and told her that he needed to be alone.  When he
hallucinates the ghost at the banquet, Lady Macbeth senses that he has done wrong but
she is not sure what deed has been committed.