If y'all's bitchasses are gonna shame on John, you better as Hell shame Mary a million times harder. As shown in Supernatural, John was a good guy before he ran off with Mary. Yeah, sure the Navy fucked him up. But he was also married to a narcissistic controlling freak that cut him down and argued with him on the phone in front of her four year old son when she could've just as easily walked into the other room to take the call. But she didn't. Why? So, little Dean who's too young to know any better would feel sorry for her and try to comfort her, completely oblivious to the fact that Mommy is the problem. Yeah, sure she died on that ceiling with John watching in horror. But she was also the person who sold her son to a Goddamn Demon (years before he existed) just to resurrect her boy toy. She was warned by Azazel, that if she stayed out of his way, nobody would get hurt. Her first death was her fault and her fault only.
John was her getaway train. He man to use and manipulate as she saw fit. Just to run away from her Hunter life. She tried to play it like she was so much better than Samuel when she grew up to be just like him. And if you've ever seen any High School movie, you would know that you never trust the "pretty girls".
Of course, even before her resurrection, back in the episode Home, realizing that her sons had no recollection of her, she saw this as her opportunity to play innocent mom, manipulating them even as a ghost. And when she does rez (at the hands of that bloody Amara), she does the same all over again. Tries to play the mom that cares what happens to her boys, knowing that that is what a normal mom would do. Like, yeah, Dean lost it on her but his Aquarius ass forgave her way too easily. In all honesty, if Azazel never came to that house that night and the boys grew up normal with a mother and father, John would've died at war and Mary (not liking strings attached) would've ditched Sam and Dean at the nearest fire station and fucking ditched. Mary plays the good mom, protecting Sam from his captors, supporting Dean's friendship with Cas, even being lenient about an alliance with a freaking Demon (Crowley). But she shows her true colors soon enough.
She emotionally manipulates Mick Davies into viewing her as that perfect mom/girlfriend so that he wouldn't suspect a thing when she does decide to seduce and manipulate his best friend. This also making Mick a good pawn for later use, a backup plan if you will in case her original plan goes south. Now, with Arthur Ketch, we get a real glimpse of the woman she really is. She takes a man heavily burdened with trauma, never really knew love or affection, that is fiercely loyal even if he knows it will kill him, and is harsh enough where nobody would ever consider him a victim and she plays that boy like a fiddle. Manipulating him, playing with his head, giving him a taste of love only to take it away, playing victim when he was fucking trying to save her. All of this just because she's a petty whore that only cares about herself. She turns the remains of her family against him, paints him out to be this evil sadistic killer, even turns his first love against him, and then she kills him, shooting him twice. First, in the shoulder, then right in between the eyes. Afterwards, discarding his body in a ditch like he never fucking mattered.
Let's not forget that like all evil whores face to face with immence power, she groomed a child under a year old. Made Jack trust her, rely on her, when in all reality, he would've been safer with the Apocalypse World Michael, himself. And for this (and countless other things I could mention), her second death wasn't anything if not deserved. Hell, it would've been better if Jack purposely obliterated her ass. I mean, what kind of a dumbass hoe fucks with an emotionally and psychologically unstable child with immense power? She was fucking asking for it. Now, how about we do the entire universe a favor and make her soul simply not exist?