Anger often acts as a pressure gauge for stress you haven't been able to...

https://www.bookmarking-jet.win/anger-is-rarely-just-about-temper-it-is-usually-the-pressure-of-unspoken

Anger often acts as a pressure gauge for stress you haven't been able to release. When you carry that weight, it shows up as a tight jaw, aching shoulders, or restless sleep