SO LIKE I'M CONFUSED HOW DOES LADY MACBETH EVEN DIE???

I'm not really sure how she dies and I really would like to know, only because she's a bitch and uncool. In the beginning of Act V, Shakespeare mentions how Lady Macbeth has gone crazy. She is sleep walking in her sleep and doing strange things while being asleep. (This is more than likely because the guilt of killing Duncan is getting to her). The doctor concludes that she needs a priest's help, there is nothing a doctor could do for her because she is insane.
Macbeth is about to go into battle whenever Seyton returns and announces the death of Lady Macbeth to him. He seems unaware of what just happened and says how she should have died at a later time, at a more convenient time.
But they fail to mention how she died.
So as the reader, we just assume she got sick or something.

MACBETH IS WHIPPEDDDD

Am I the only one who noticed how controlling Lady Macbeth is?? Macbeth is basically whipped and kisses the ground she walks on. Although it was originally Macbeth's idea to kill Duncan to become King, he immediately puts this idea to rest. In the letter to his wife, he does mention it. BUT AGAIN, he puts it down quickly.
After reading the letter, Lady Macbeth is immediately thrilled with the idea and begins to plot Duncan's death. (Obviously she's being a greedy bitch and wants to be Queen) She is familiar with the witches' prophecies, the one about Macbeth being King and stuff, and she wants to be sure that these prophecies come true.
{LET ME REMIND YOU THOUGH THAT THESE ARE ONLY PROPHECIES.}
When Macbeth finally comes home, he is bombarded with her new infatuation and plan to kill Duncan. But Macbeth is not sure of this, he hesitates because Duncan is his cousin. Whenever Lady Macbeth hears this, she is enraged and begins to put Macbeth down by calling him a coward, hoping this will encourage Macbeth to kill.

If you're in a controlling relationship like Macbeth and Lady Macbeth, and maybe perhaps you' re "whipped", please call (1)800-438-4357.

So after researching about this stupid meaning, different readers interpret this meaning differently. Some people say it is the foreshadowing of the entire play. I suppose this makes sense. FAIR IS FOUL AND FOUL IS FAIR. Macbeth killed Duncan in Act II. S finally is Act V Macbeth is put to death and be headed. (Meaning he deserved this because he killed someone, so he got what was coming to him).
Other readers believe it is actually the entire theme of the play. What is fair to one character is foul to the other.

WHAT DOES "FAIR IS FOUL AND FOUL IS FAIR" EVEN MEAN???