The Syphon Filter series. Overlooked sibling of Metal Gear Solid and Splinter Cell, and for good reason—it wasn't really a stealth game, and its gameplay was rather simple.

The third is often regarded as the weakest of the main trilogy.
Despite that, it's unique in that its missions were almost entirely flashbacks from the perspective of the various special agents in the game, all who seem emotionally stable and focused on their objective.

But its repetitive and homogenous maps, dark low-res graphics, and a grave ambient soundtrack present in most of the levels join with the narrative to convey a dreamlike and disturbed recollection of events that implies a larger mark on the game's protagonists than they let on.
Call me a schizo, but these factors accidentally produced a somewhat psychologically accurate retelling of their experiences as soldiers.