It’s reasonable to feel hurt and disappointed by people when they do disappointing things. However, it’s a complete mistake to apply these feelings, beliefs or standards to anyone new, or to people in general. Every person you encounter and meet for the first time is of potential value to you, in some way. Each new person is ‘tabula rasa,’ a blank slate. They are worthwhile until proven otherwise. Yes, more will show themselves as not worthwhile than worthwhile (at least, worst case). Yet the presence of 10 disappointing people says nothing whatsoever about the 11th you will meet.
Try to focus less on how so many people are not living up to your standards, and instead try to celebrate the fact that you have standards and can identify them in people as you go through life.