In "Macbeth," what was Lady Macbeth writing on her letter while she was sleepwalking?

Chances are that the paper was either filled with gibberish or it was blank.  It's possible, even, that the letter was actually the one that Macbeth sent to her telling her of the witches' prophecies.  Ldy Macbeth's sleepwalking is caused by the guilt she carries for her part in the murder of Duncan as well as the other murders that have taken place in the play.  In Act 1. sc. 5, Lady Macbeth received Macbeth's letter telling her what the witches told him in scene 3.  She then decides that she and Macbeth will do whatever it takes to make him become king - including killing Duncan.  She asks the spirits to fill her with cruelty and to make her strong and masculine so that she can commit murder.  She seems to have no problems with this strength until it comes to dealing with the guilt.  If Lady Macbeth is writing anything at all, it's probably a confession because her words from the sleepwalking scene are a confession.