People do come in all varieties. Some don't think the same thing you're thinking and their actions may come across as self absorbed, inconsiderate and rude. The list is endless. I listen to a comedian named Bill Burr and one day on his podcast he was talking about his anger issues. It was suggested to him to say to himself "of course that person did that blank". He gave an example of a 4 way stop sign in which a white lady in a white Mercedes Benz didn't bother to stop when he was at the intersection first. He said to himself "of course she went through her stop sign without waiting because that the world she lives in". I cleaned up his comment.

You say of course to suggest that something is normal, obvious, or well-known, and should therefore not surprise you or be upsetting.

I sometimes use this tool myself and it makes a situation funny instead of making me mad.

Nothing works 100% so I keep a lookout for "red flags" so I don't let a situation get too far along before it's too late. If a situation has more red flags than a Chinese parade then you have to forget dealing with it and leave.

I'm not a psychologist or and expert so nothing I say I care to backup or debate.