Well, it depends on how you define "disease." IF it's a negative medical condition, then yeah.
But I think that there's often a desire (human, fallen nature!) to excuse wrong behavior... to make it not our fault. SURE, sometimes, this is an unavoidable medical condition that has NOTHING to do with one's diet or lifestyle, our choices. But I don't think this is true 100% of the time. There probably ARE psychological issues often at play (so a mental disease?) but I'll leave that to Dr. Phil.
I think it's healthy (in many ways) to accept accountability and "own up" to our choices - however difficult those might be. There will be little in the way of healing until we do.
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