The only thing you are 100% in control of is the way you feel about the things that happen to you in your life.
If you hold open a door for someone who doesn’t say thank you, you can look at in two ways.
You could get angry with them for being so ungrateful.
You could think that the pleasure is in the giving. So you gained by being able to help someone else.
You can not control how someone else behaves but you can control how you feel about what happens.
If you can choose whether to be happy or not, why would you want to choose not?