Why do you care so much? You know she came as a visitor, you aren't responsible. Period.
If this was a Supervisa application it would have involved a lot more than a simple letter of invitation.
I know it must be a stressful time for you, but this really isn't something you should be worrying about. Forget about this.
The other reason I care so much is that the family from Toronto (mother in law sister in law) came to the funeral and are trying to extort money that belongs to my wife that is legally transferred to me the husband. That is when they told me she wanted to stay longer and want me to pay for that. I'm trying to get my letter of invitation revokes she can't legally demand anything from me. The Law requires black and white on paper regarding it. I just need a peace of mind that nothing can tie me to her.