Life is too short to be pissed off
When has being pissed off ever made you feel better? Think about it. Never. It's a reaction your mind have been conditioned to trigger in response to vile feelings, such as anger, jealousy, and fear. And most of the time we accept this, writing it off as "natural".
Break the loop. Start recognizing your behaviour and ask: Am I being who I want to be? Do I want to be the person who freaks out when the supermarked runs out of milk or the bus is late or someone accidentally spills beer on my shoes? Nobody does, but most are.
Shit happens. Every second you spend being pissed off about something you can't change is a second you could have spend being happy. How many seconds going on days are you willing to waste being pissed off?
Work on your getting-over-it acceleration. Be the Ferrari. You'll like yourself better and others will too.