Confused Musical Presentation

first ide try to eliminate the system by asking someone else without a hearing problem to listen .the effect you describe is quite dramatic and noticeable. even though to me it makes sense that the small mic\speaker in the hearing aid are overloaded. 
in my system (nuforce icon hd arcam delta 120 b&w dm 580)i used to enjoy 70's ecm  albums (early metheny jan garbarek ralph towner)but could't enjoy led zeppelin everything collapsed like you describe so this helped with clarity
swap all the tubes to nos ge jan tubes
get a loki or some transpenant mild eq
get the ifi itube (it has a ge tube it's adding to the preamp) use it with zero gain as a buffer before or after the preamp
get really nice open headphones and amp i'm happy with hd700 and the icon hd but according to your system you have a finer taste than me so try and see what you like maybe staxx

One thing is absolutely true is that I CANNOT discern audible ques in a crowded environment!

What I was afraid of. If this happens even without hearing aids then sorry to say its not them its you. Oh well. Natural process, happens to us all, just in your case you got a lot of help and a big head start. 

So your trauma has resulted in a condition of not only loss but also inability to distinguish individual sources in, as you say, a complex environment. You are not alone in this. Lots of us experience this to one degree or another, and it only gets worse with age. Its so common almost everyone with hearing aids has this problem. 

So yeah harsh and brutal but I think if you face reality its painful but at least then you stand a fighting chance. No amount of delusional room treatment etc ever gonna get you anywhere. 

Since you are not the only one however then I have to think there are those who have studied this. I would begin as always with the interweb. But search, don't just ask random people, you hit pay dirt with me yes but to continue the mining metaphor that vein is played out you're down to a gram per ton if that.

Your audiologist might be able to help so ask him. What you're looking for is research or info on exercises to rehab your hearing. It could be physical but there could be a psychological component as well. Basically you have been traumatized repeatedly and now your brain is interpreting any complex sound at any volume as noise.

Not saying this is what happened, but if it was me I'd want nothing more than to curl up in a ball and shut out the world. If I couldn't do that physically I bet you my brain sure would as a protective mechanism if nothing else. Which unfortunately goes with you when you leave the battlefield.

Probably a lot of this is physical, similar to the hearing loss. But to whatever extent it is psychological, which I'm sure there's plenty going on there too, well then that would be good as at least there you stand a chance. 

Meantime, just a hunch but if it was me I'd be doing all I could to play and enjoy whatever music I'm able, and assiduously avoid whatever triggers this auditory confusion. Not just in music, but everywhere, to the extent that is possible I mean.

A side benefit, you may gradually come to gain an appreciation, or maybe recognition is a better word, for what is going on. Like, you already know its complexity not volume, and complexity of environment not just music.

One of the best psychologists I know said something to the effect that even if something is out of your control, to the extent you understand and recognize it, that alone is enough to bring a sense of relief. Might sound crazy but in my experience its one of the most sensible insights ever.

So you're a smart guy. And military, so you know perseverance. You'll figure it out. Let me know. Way I see it, probably be needing it myself some day.

Thanks to everyone for your input. I'll take all into consideration and report back later.
Mike