Already seen those. I'll add them to my first post.
And Ted Bundy.
Might make a list out of this thread.

Watched Bruiser today. Good flick!
Thanks for the tip!

Why did you ignore my suggestions?

Shutter Island
Dead Ringers (focuses on twins, though they may as well be a singular person)
Dark Tourist
Alyce Kills
Chasing Sleep

Can't edit my first post anymore so no additions there.

Didn't realise I quoted everyone but you. My apologies, sir.
I looked them up, but I didn't find any downloads.
But I'll continue my search later.

Seen Shutter Island, great movie.
Tried Alyce Kills but found it rather annoying.

Don't know the others but I looked them up and they seem interesting. Thanks!

Just done watching.
Great movie!
Didn't know what to expect but I was pleasantly surprised.

Surprised no one's mentioned Maniac yet
I Stand Alone as well.

Glad you liked it!

And I heartily second Mothman's rec for Maniac. Great film and this is coming from someone who has difficulty separating Elijah Wood from his turn as Frodo.

As for I Stand Alone, I've been meaning to see that one myself.

Forgot about Maniac. Seen it.

Don't know I Stand Alone but I'll check it out.

Afraid you might find this a little off topic but ho hum.

Still in theatres is Gravity.Also not really horror but touches on the theme of madness and is surprisingly captivating considering it is almost all Bullock. Always impressed when a person carries a film by themselves like that - Smith and Hanks in I am Legend and Castaway, respectively, equally captivating.

Of course, to experience those themes in a very isolated setting I can't recommend the Dead Space series more. So lonely!

The Chaser (to go with I Saw The Devil)

Black Swan (Portman's performance is incredible)

High Tension (personally hate the ending but some don't mind it)

Tale of Two Sisters (same critique as above)