Okay, so this is not really so much of "am I being unreasonable" as it is a "she is clearly unreasonable" but we haven't got that topic (yet) on Mumsnet.
I could tell you what she has done. But I don't need to because I know beyond a shadow of a doubt that it is she who is unreasonable.
So, who else has a crazy wicked old bat for a mother and what has she done?