Worlds Within (2014)

Following his wife's suicide, Henry Walton, an experimental psychologist, becomes tormented by feelings of grief and guilt. Placing blame upon himself for her death, Henry becomes obsessed with the idea of reuniting with the woman he loves. After performing an experiment on himself with a new sensory device, Henry's psyche begins to unravel. As a result, he starts to walk a fine line between reality and delusion, making Henry's world become increasingly fragmented and distorted by the day. Manifestations of his feelings begin to appear as harrowing delusions that cross over in to Henry's waking life.

Unfortunately the movie Worlds Within is not yet available on HBO Max.