I am currently seeing a consulant psychologist to do with my PTSD and have been discussing rages in depth because I have them. It is very difficult control them but the psych pointed out I know when they are coming on and have to learn to recognise the flashpoint and walk away from them. However as you say that is not always possible.

I am lucky now to have a partner who is prepared to understand PTSD and to walk with me through it. She is very adept at dealing with my mood swing and finds absolutely non confrontation is best and will steer me out of harms way. I trust her so it helps.

My last partner - my wife of 18 years - just exaccerbated everything and argued it was all made up!

I would suggest all you can de is effectively recognise the triggers and work together to avoid them or move away if they are there.