It might take some sleuthing - I have been doing the same for my meltdown/shutdowns. By paying careful attention to things that lead up to them (advice from my doctor), I am able to identify things I was not wholly aware off. Not everything can be controlled, but when you can start to eliminate some, it can make a difference.
For example, I would (and do) get angry about injustices related to society similar to you. By being super aware and writing things down when I notice, I caught that there was a certain smell that triggered some really angry thoughts - which just took off from there. I thought the smell was "just one more thing" that bothered me, I was surprised that it was actually at the beginning of my thought storm as a casual link. The "people" stressors and chaos are one thing, I think it is important to remember that the physical things add up, too. When my mind is going, there is often body discomfort involved to set it off. It is hard with a family, but is there one refuge in the house - garage - what have you - that you can set up as a sensory or low-sensory haven? Is there somewhere nearby you can go - a library, a late night store that is quite empty, just a walk - maybe with an MP3 player to crowd out thoughts?
Sometimes I find activities, such as memorizing Pi, a way to crowd out my negative thought loops because I focus on the numbers and putting them in order - it feels so good ordering something. Pretty soon, Pi is all I can see for a while.
Is there something that you can hold or touch that gives you comfort?
I suggest playing around with ideas such as these, experiment. I know you are worried about your family, but it is not fun for you either. You - and they - deserve to feel better. Be a detective and I hope you find something that works so you feel better soon.
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Great spirits have always encountered violent opposition from mediocre minds - Albert Einstein.