We are only hurt if we choose to be hurt. We are only sad if we choose to be sad. We are completely free to do and feel as we wish. It is all an illusion of the mind. Thus choose to be happy, choose to feel good, for if it is all a choice, why not pick the choice in which you’re happy?
The biggest mistake you can make is to base your happiness on others. If your happiness depends on other people, then you will be sorely disappointed and you will be sad often.
You are not entitled to anything. Stop having expectations of other people. People are going to do what they are going to do and there is nothing you can do about it. Let them do whatever they want, for you do not control them and they are free. Thus it’s stupid to be angry at others or have expectations of them, you are only setting yourself up to disappointments. You are expecting something that is not based in reality. If a person has never behaved in a certain manner, or you’ve never observed them doing so/known them long enough to observe, why are you angry that they didn’t behave in the way you wanted them to behave? Why are you expecting them to behave how you want them to behave? That’s stupid! They are going to behave how they want to, and you can do nothing about it. Stop having expectations of people. At the same time though, you don’t have to conform to other people’s expectations. You are free to do whatever you want and they do not control your life. Thus live by the modified golden rule, treat others as you would treat yourself, but don’t expect that treatment reciprocated from them. There is absolutely no reason for you to have that expectation. It’s an imaginary fantasy that will never happen.