Similar things happen to me. People tend to have a harsh reaction when I undermine their emotionally-charged beliefs with an effort to understand a situation.

To me, it seems like two different ways of dealing with the negative emotions from a frustrating situation are at odds with each other. I've caught myself doing both. Fuming, "that guy is just a dumbass"-type rationalizations quickly patch me up and let me move on. Hatred is kind of cathartic. Maybe in your mom's case it was something positive, having faith in a system and emotional attachment to that faith. Like learning to love something after living with it so long.

On the opposite side is trying to fit the situation into a bigger picture, really trying to understand why it's happened, and using that information to calm yourself somewhat. Understanding that people have habits, and aren't totally 100% in control of what they do. Or that an imperfect system that our society is based around could stand for improvement. I feel a great sense of calm when I rationalize things this way (or at least feel like I have). Almost...a smugness.

I don't think you're an asshole. I do think the way you rationalized those situations brought you closer to the truth. But also to a disagreement with your people. Perhaps their reactions made you feel like an asshole because you brought a conflict where they thought there wouldn't be one.