I see that the mods are now all over this thread.
OP, seriously, don’t take this treatment. If you are intending to spend the rest of your life with this womans daughter, you better get the ground rules sorted out now / in the early stages.
Pay no attention to the wishy-washy, spineless comments advising you to bite your lip, go for a quick walk, etc.
What gives this woman the right to kick off when she likes, and have everyone else then cowar, tremble in fear and stay passive until the tantrum is over ?.
And you don’t have to fix her either, all this talk to her stuff, eh ?.
What ?, is the OP some sort of head doctor and he is going to help future MIL with her issues ?.
Forget that. She is a big girl now, she should behave like one or get gone, imo.
Its a two way street, if she cared, she’d be making the effort to get along with you, not ranting about you not driving slowly enough for her latest home video.
You are her host, not her whipping boy !.
EDIT:
Yeah, that Dayus thing didn’t make any sense to me.
More MOD magic ?