How do I stop feeling worthless after customers yell at me?

You stand all day while strangers unload their anger on you over things you did not cause and cannot fix. Then you go home feeling like you are nothing. That is a heavy way to spend your days, and the fact that it wears you down does not make you weak. It makes you human. Here is the thing to hold onto. The customer yelling about a price or a policy is not really seeing you. They are venting at whoever wears the uniform. Their anger is a fact about their bad day, not a verdict on your value. When you take it home as proof you are nothing, you are letting a stranger's worst moment define you, and they have not earned that power. Put the uniform down at the door, in your mind as well as your body. What happens on the floor is a role you play, not the whole of who you are. Find the people and the moments that remind you of your real worth, and let them count more than the yelling. You are not nothing. You are a person doing hard work with patience most people could not manage. Do not let a stranger tell you otherwise.