Kether Donohue, Aya Cash, Chris Geere and Desmin Borges star in “You’re the Worst.” Aya Cash, Chris Geere, Desmin Borges and Kether Donohue Who’s The Worst? by Jay S. Jacobs The missing component in most romantic comedies is a refreshing dose of hardened cynicism, and FX’s new series You’re the Worst has a heaping helping of that special ingredient.  The show is basically an anti-Valentine, a perfect bouquet of pitch black flowers which earns its laughs through a jaded look a