S., you have your hands full with your brood.
I think your training in martial arts is a perfect way to channel energy and anger in productive ways.
But there are other elements of PTSD that require time for meditation, time for nurturing oneself, time for exploring one's gentle side.
I have a three year old, and I haven't yet been successful in asking her for my own "time-out." Whenever I'm stressed out and having flash-backs and we're home alone together, she gloms on to me, and that doesn't help either of us.
Your kids are older, though, and can understand your need for quiet time.
When a PTSD episode comes up, I try to use art, journaling, herbs in strong tea infusions, exercise, gardening, and talk therapy to help me calm and process through things. You may be able to encourage your kids to do some art (collage? journaling? bookmaking?) alongside you while you explore your own issues?
I struggle with this in an intense way and haven't found a perfect solution. Courage to you!