This is a pretty good insight. Having either PTSD or at least some subset of it, since six years or so, I don't know if I would have been able to understand it prior to my trauma.

The after effects alone on the body and brain are extreme, and then the changes they leave appear to be semi-permanent (it takes a long time to calm down, if at all for some, I guess). Perhaps the best way to explain it to someone is as a chronic illness, so that the matter of "choice" is taken out of the equation. The massive surges of adrenaline and anxiety attacks can't be just "let go".

As for avoiding suicide, climbing up from rock bottom, and finding psychologists to be largely "only human" and not quite clever to figure me out, I've built up my own bag of tricks.

The most useful, also good for depression, has been to take note of the things I enjoy, so when I hit rock bottom, even when those things bring me no pleasure or even desire to do them, I tell myself that they can, but I have to wait for the extreme emotions to pass, which can take days, perhaps weeks. For me this is the desire to build things with electronics, into the area of robotics. It's something I've been meaning to do since childhood, but never made time or had the concentration for it. Now I do. Finding that one thing to be even a little bit passionate about, where that feeling of passion is real, and not just a wish, can be difficult.

Additionally, the last time I noticed my mind thinking about suicide, I recognized this as a slippery slope. It forced me to quit my job to get out of a situation that was too stressful for me. The effects of PTSD on working life and work/social expectations are incredibly taxing! :)

Anyway, I could ramble on.