This one seems like a no-brainer: flushing meds in the present + appearing weary and alone in the future = Toby relapsing. A trailer clip also shows Toby reading a medical pamphlet about antidepressant withdrawal symptoms. Going off antidepressants without a doctor's advice and without a slow withdrawal plan is about as bad a decision as a patient can make, so there's definitely going to be consequences in future episodes. We know already that the ending of his first marriage sent Toby into a depression, which leads us to our next theory . . .