The ending even had the main sociopathic girl killing her sister and the neighbor jump roping bitch by lung transplants due to her sister's cystic fibrosis disease.

Everyone dies on this one due to "secrets" being revealed by each friend, and a little girl ghost kills them one by one either by luring them to the highway until a truck runs over them or falling in the basement when doors keep slamming shut. I liked the twist subplot of the killer being an adopted brother of the ghost girl before the accident happened at the start of the movie. Weird-ass shit going on here.

Speaking of the ending, it would've been nice if this movie had one.
I realize they're trying to go for the 'assumed' ending, but when your final scene depicts Liam Neeson duct-taping broken shooters to his fists in a last stand against an alpha wolf, you might as well go all the way with it.
Instead, the movie ends at the last possible second before the fight ensues.

There is a post credits scene, which doesn't really explain anything.

these guys surviving ridiculous circumstances - (circumstances which should have surely killed them 15 minutes into the film), all the while fighting off poorly rendered CG wolves, jumping off cliffs and surviving, making working tightropes out of shirts to cross chasms, and they cap it off with Liam Neeson taping shooters to his fists.

After all that they tack on a non-ending in an effort to induce a poignant cliffhanger, so they can try and get the audience to empathize with a character that's barely been developed.

You get a very clear resolution to the film. I maintain that the ending is as perfect as it can get for this story. There is only one possible outcome to one man vs. a pack of wolves, and it isn't guy kills all wolves then a rescue helicopter flies over and everything is just dandy bars. The film ends with Ottway being done with running, making his stand, and knowing full well that he's done. But he's going out on his own terms. Not drowning in a river or falling off a cliff. Once more into the fray. That's the resolution, not something as pat as whether he gets rescued or not.

The main problem with The Grey was that it was marketed as Liam Neeson vs. Wolves, and that's not what it is at all. Just because the premise and some of the events of a film are preposterous, it doesn't mean the film itself was. There's not a lot of films that have genuinely realistic premises and characters. The characters are developed enough, it's just in a much more subtle way than most films. I didn't find any of them to be stock character like you might think you'd see in a film like this.

R.I.P. To M who died of an earlier gunshot after that dramatic rescue from Bond who killed that guy in No Country for Old Men.