Next to Her (2014)

Cheli, 27, is raising her mentally challenged 24yo sister, Gaby, alone. When the social worker finds out that Cheli leaves Gaby alone in the house while Cheli is at work, Cheli is compelled to place Gaby in a day program. For the first time in her life, Cheli shares Gaby's care with someone else; her daily routine collapses and the huge void left by Gaby's absence makes room for a man in Cheli's life in the shape of Zohar, who inadvertently creates a chink in the sisters' symbiotic relationship. While Cheli hangs on to Zohar's love for all she's worth, her inability to have a normal, intimate, and emotional relationship with anyone but her sister forces them into a twisted threesome, where boundaries between love, sacrifice, nurturing, and torturing are crossed.