Reading through this, I dunno if I can help here since my dilemma is somewhat similar to yours. An awkward little chicken and egg scenario, isn't it?
Though you do have the benefit of different centers...
At risk of this being too simplistic, can you distinguish whether it's oversensitivity to (and attempting to control against) anxiety-inducing situations or disindentification with your frustration and not feeling like you have the right to assert yourself that takes up more of your energy and focus?
Of these, if I'm interpreting them correctly, I would say I'm more focused on sensitivity to/prevention of the anxiety-inducing situations. I need to be in control enough to prevent them. And when I sense one happening, if I can, I will snub it out, fast.
Example:
Dad, sister, and I go out to eat. Dad brings up a "hot topic" (such as politics) that sister an I disagree with. I may calmly engage for a while, but sister and dad will become more heated. As I sense this, I immediately
demand a subject change. We are going to stop talking about this now. I may snap at them and it will be awkward for a moment, but I don't want the stress of having a heated argument in public (especially since the two of them won't be quiet, their voices carry). That kind of situation causes me stress and hell no I'm not letting it happen if I can help it.
But that is much easier to do with my family members, who I'm more comfortable asserting myself around, than strangers. If I'm at school or work or something and two people get heated (which causes a stress-inducing situation), I'm usually just a helpless bystander who is upset but doesn't know what to do. If I have any sort of weight with the people involved, I'll try to calm them down.
Those are both people-oriented examples, so let me give an example of an anxiety-inducing situation that is not people-oriented.
One time, my first semester of college, I read the directions wrong on a take-home quiz and got something like a 65%. This caused me to go into meltdown mode. My mom spent an hour or so trying to calm me down and talk sense into me but nothing worked and she literally gave up and left me there mid-panic attack because it was hopeless. Complete shutdown. I reject every idea and refuse to take any action. I feel hopeless. The atmosphere is super heavy. I can only see the bad and not the good. And this is a situation I was not anticipating, because I thought I had followed the directions but apparently I had not.
Other not-person-related situations that have caused me anxiety are times when I have had computer troubles. It won't start properly, or some aspect of it isn't working, or some update goes wrong and I have to run system restore. Again, shutdown mode, hopeless feelings, etc.
Those mostly all relate to my
reactions to stress, though. Prevention of stressful situations is important to me but not always possible.