Stoicism, nihilism, various forms of the Buddhist tradition all seem to focus on the message: "You are the leaf, not the river".
You can't control the river/universe. It will happen with or without you. Worrying about it or what it will do to you is almost a waste of time and energy. Like if the sun were to explode right now, it almost wouldn't warrant reaction. Because the outcome is set. Any reaction is going to be erased in 8 minutes.
On a much smaller scale, you also can't control other people. They're going to do their things. If something they do affects you, do what you can to mitigate or enhance the effects depending on if the results are wanted or not. Like if I were to get fired from my job, there's little I can do to change that outcome. Even if I wanted to. So there's no point to dwell on it. I need to focus on the next thing now. I would pack up my things, scrub my work machine, turn it in, and go home to look for a new job. No crying, no yelling, etc. Disappointment, sure, but I got shit to do.