Awuh and Dee bring up the very important word expectations.
Imposing them on others, wanting to control outcomes, expecting that others will want, do, etc what we want....these are futile most of the time, and certainly cost us peace and the ability to be grateful for what we do have, how things do happen in our lives.
Learning about boundaries and standards- for my own behavior- and not imposing my expectations (i.e. What I want or think is right) on others helps me stay away from things like resentment, which can easily build if I focus on the wrong things.