uncommonly advantageous

Can your girl blorbo be trusted with a firearm?

-yes, she can be trusted and she’s responsible

-possibly? Maybe? I hope?

-probably not

-do NOT let that girl near a weapon! Dangerous!

Anyway:

Henry loving Fanny is confirmed by the narrator and without irony. He loved her, "rationally and passionately". He also slept with another woman. To him, this is entirely compatible:

He was entangled by his own vanity, with as little excuse of love as possible, and without the smallest inconstancy of mind towards her cousin.

This view is confirmed in In The Time Traveller's Guide to Regency Britain by Ian Mortimer, where the author explains that in that time period, visiting a prostitute for "just sex" was seen as morally better than having a mistress, because it interfered with the emotional bond of a marriage.

Mary Crawford knows this and is expecting it to happen to her, just like it did to her aunt. She is cynically hoping that at least whomever she marries is rich and discreet. It is only in Edmund that she learns to hope for better:

for Mary, though perfectly resolved against ever attaching herself to a younger brother again, was long in finding among the dashing representatives, or idle heir-apparents, who were at the command of her beauty, and her £20,000, any one who could satisfy the better taste she had acquired at Mansfield, whose character and manners could authorise a hope of the domestic happiness she had there learned to estimate, or put Edmund Bertram sufficiently out of her head.

Elizabeth Bennet fanart in an art nouveau style - watercolour and ink

Inspired by the ‘95 miniseries design (the only true adaptation yes I will die on this hill)

It is not.

Mrs. Bennet sucks too.

The most recent example that a few people have added:

She is not hauling ass. (And poverty is an exaggeration, they'll have £250/year.)

She is screaming "The house is on fire!" while she herself pours more gasoline on it and does not call the fire department even though the cell phone is in her hand.

She says she wants her girls to get married. What effort has she contributed to this goal? Let's review.

❌ She has done nothing to raise her girls to have good manners, accomplishments, or education that would attract good men.

❌ She has done nothing to save money for her girls, again to either attract husbands or protect them if they never marry. (And they were rich, saving would have been very easy, but she and her husband were too selfish and lazy to do it.)

✅ She buys her girls dresses and ⚠️takes them to parties. That is literally it. The only thing she does to help them, and she does it so poorly that she actually makes things worse for them with her poor manners and management of her younger girls.

This isn't even getting into how abysmally she does as a mother in terms of loving, understanding, supporting, and guiding her children in aspects of their lives outside getting married...

She hurts her girls just as much as her husband, just in somewhat different ways.

TL;DR: