Is there a game like this: FPS/similar where enemies don't auto-attack?

No.

Deus Ex Human Revolution comes to mind. You can complete the game, apart from the boss battles, without getting in firefights, and there's even an achievement for it if you don't kill anyone. There are non-lethal weapons in the game for that too. Worth checking out, a really good FPS/RPG blend.

I don't AI is that advanced yet. I know one thing The Last of Us showed off in its debut trailer was AI like you describe, people were disappointed when enemies were dumbed down at release.

postal 2 have many difficult lvls, people can attack you or not, and if you hold your gun or not have his incidence...

Hm, it is hard to figure since the purpose of such games is mostly survival. There are two games coming to my mind:

• The first one is Resident Evil 4. Every enemy you encounter will start to attack you (if they see you or know that you are there) but basically you are the outsider breaching into their territory so it is more of self-defense. Althought they are doing weird Things and have kidnapped someone ..... But it may fit in what you are searching.

• The second one is DreadOut. A nice horror game in the spirit of Fatal Frame. The enemys here a ghosts and while a lot of them start "attacking" you if you come near them there are also some which ignore you or only annoy you and you can pass them without harm. But fighting is not the main focus of the game anyways.

Amnesia: The Dark Descent maybe? http://store.steampowered.com/app/57300/?snr=1_7_15__13 I checked your profile and you own it but never played before. If you looking for horror without constant fighting scenes, well, this seems to be something for you. Game is more about story, atmosphere, avoiding all fights etc... so this is just pretty dynamic horror-adventure game in 3D.

@ +Call of Cthulhu: Dark Corners of the Earth, of course. pretty same story as Amnesia but there are fights after half of the game http://store.steampowered.com/app/22340/

@ now I see that you own both Alan Wake games and never played them as well. American Nightmare have more fight scenes but part 1 is more about escaping and story, fine Stephen King's style. my recommendation to give'em a chance.

@ another title, you may be interested in to check it out - Condemned: Criminal Origins http://store.steampowered.com/app/4720/

@ FarSky, in your library too http://store.steampowered.com/app/286340/ something different, open world adventure under ocean waters, with tension and emotions when you exploring more dangerous parts of the pretty small randomly generated world. quite short and easy casual survivalist game with some minecraft/classic survival components. clearly defined main objective, that's good thing in that kind of games.
the world is dangerous but not in a pushy way, you may fight with everything but no need to do this all the time. I had lots of fun with FS.

In regards to "similar", Hitman? Enemies won't attack you unless you trespass in specific areas, or you draw your gun.

The first System Shock actually had a setting that made it so that enemies would not attack you on sight as well.

S.T.A.L.K.E.R.?

Amnesia, STALKER, Far Cry, Deus Ex, any of the main Metal Gear games, and practically every stealth and survival suspension horror game ever.
Oh yeah, and many Hitman games.
And Dishonored.

Now that ice thought about it The Forest has ai like that. They are pretty unpredictable whether or not they're just souting, they will attack, or run away and check back later. Pretty intense.

Rust could be another good one. It's not NPCs though, its real people as 'enemies' so... pretty unpredictable there. It can be really tense.

haven't played it yet, but you might wanna check out Outlast