Stressors and depressive symptoms have been associated with medication nonadherence among adults with type 2 diabetes (T2DM). We tested whether these associations were exacerbated by obstructive family behaviors or buffered by supportive family behaviors in a sample of 192 adults with T2DM and low socioeconomic status using unadjusted and adjusted regression models. We found support for the exacerbating hypothesis. Stressors and nonadherence were only associated at higher levels of obstructive family behaviors (interaction AOR = 1.12, p = .002). Similarly, depressive symptoms and nonadherence were only associated at higher levels of obstructive family behaviors (interaction AOR = 3.31, p = .002). When participants reported few obstructive family behaviors, neither stressors nor depressive symptoms were associated with nonadherence. We did not find support for the buffering hypothesis; stressors and depressive symptoms were associated with nonadherence regardless of supportive family behaviors. Nonadherent patients experiencing stressors and/or major depressive symptoms may benefit from interventions that reduce obstructive family behaviors.