alien: isolation
this one's good, you can get it for real cheap nowadays and it's not as punishing as other horror games. Very fun.
Amnesia is a classic, real scary but it's very compelling. plus, the game's actually short (in a good way), it's just that it feels like it takes a million years to complete because you spend most of it huddled in a corner.
SOMA is an incredible game, but it's far more cerebral than typical horror fare. If you just want something scary and fun, i'd say wait on this one, because SOMA is really deep and makes you sit back and think about your actions. But, if you're interested in a horror game with a very compelling story, SOMA is the best.
I've heard very good things about resident evil 7, but a lot of people say the way to play it is in VR.
INSIDE isn't a conventional horror game but god damn if it ain't eerie as hell lol
also, the people who mades Layers Of Fear are making a new game called Observer, Layers of Fear was pretty dorky and not really that scary, but their new game looks really interesting, so be on the look out