A ton can change just based on your mindset. There’s a lot of that subject in stoic and (secular) Buddhist philosophy. It’s not sticking your head in the sand, but rather practicing being more in control of your mental state while processing the things you need to process.
For instance in Buddhism one of the three poisons is attachment, or sometimes called greed. Having high expectations of other people and relying on their actions to inform your mental state is just setting yourself up for failure.