Lydia is a game that is as hard to write about because of its brevity as its difficult subject matter. With a short runtime-- most people seem to have spent about 1-2 hours with the game-- and a small price tag-- $4.99-- there's not a ton to see or a lot to write about that doesn't immediately get into spoiler territory.
That being said, Lydia is a story-driven adventure game that has you playing as a young girl dealing with the substance abuse of the adults in her life. In fact, it is based on the developer's own experiences with this subject matter, making it a particularly heart-wrenching journey. The game uses a lot of metaphorical imagery of distant places and "boogeymen" to help express the difficulty of coping with these problems as a child.
Its creepy atmosphere alone earns Lydia a place on this list, but for me, it's the mundane horror found in the everyday ways that humans and completely destroy themselves and their families that really makes this title so gut-wrenching and ultimately effective at delivering its mix of message and horror.
Lydia is available on Steam for $4.99.