We have a road near my house that narrows from two lanes to one. The right lane ends, with a warning "merge" sign. I drive up this road frequently. It has been interesting to watch how different people respond to this merge. Some people signal, find an opening and merge in, as directed. Others speed up and merge. Others force their way in, occasionally pushing the person in the continuing lane into the center strip if they don't want to play bumper cars.
I used to get annoyed when people didn't drive by the rules, but what I finally came to realize is that I cannot control what other people do. I can't change them. I can't fix them. I can't control them. The only person I can control is myself. I am learning how to adjust when others act in unexpected ways.
Adjusting to those around you can be a wonderful thing! Instead of being frustrated that the person who is supposed to merge is pushing me out of my lane, I can slow down and let them in. Yes, they may be being a jerk, but I can't control them, remember? I can only control me. I remind myself that I just did my good deed for the day. I can't know why people do what they do. But I can adjust, and I feel better when I do. Imagine how wonderful it feels to not let other people have the power to ruffle your feathers. (Yes, I do realize you are not a bird.)
This is not only true for driving, it is also true for all aspects of life. Just as we may be surrounded by cars on a road, we are also surrounded by people everywhere we go, likely even in our own home.
I cannot change, fix or control anyone else. I may not know why someone else does things differently than I would. But I do have control over one very big element - myself! I can choose to be calm, patient and understanding. I can choose to steer clear. I can choose to get upset and frustrated. It's my choice. I get to choose how to adjust, and so do you. So next time someone cuts you off, remember that your response is truly your choice.