struggle to breathe properly, extremely constipated....

Hi, thanks in advance to anybody giving their knowledge to help me.
I'm 23 years old, and I seem to have a problem that nobody else does, and I've had it all my life.

I am constipated constsntly, I have no energy to get up and do things, my stomach is constantly bloated and I struggle to breathe properly, I eat a strict chicken/broccoli/water diet, if i eat anything else my symptoms all get a lot worse. Especially with complex carbs like rice and potatoes etc. It also affects my behaviour, I am 10x more irritable and get annoyed by things really easily. I have been up to hospital a few times when extremely constipated and they've found a huge backup in my system, and had to flush it all out with enemas etc.

Supplements I currently take, all of which help.

Omega3 fish oil, pre/probiotics, Miralax, coq10, glutamine, creatine monohydrate

There have been a few periods of time (1-7 days) where I have felt amazing energy, constantly motivated to get up and do things, and these have been the best days of my life. Then with no dietary changes whatsoever, I go back my normal symptoms again. I literally eat like a caveman, NO sweets or sugar, no coffee, no nothing except chicken broccoli and water. I drink plenty of water.

Iron and copper supplements make me a lot worse, as do taking amino acid supplements.
Fibre which seems to help everyone else makes my symptoms a lot worse and even more constipated/bloated, even with drinking litre after litre of water.

I have had every single test at the doctors, hormone levels, thyroid, vitamin and mineral deficiencies, iron, you name it I've had it..

I have a large family history of autism/asperger syndrome, I don't know if this has anything to do with it.

I cannot work, I have no girlfriend and no social life as I am always too lethargic to go in town when people ask me etc, I am currently living on disability benefits and spend all my time playing on Xbox/trying to find cures on google. I am seriously considering just giving up and ending it all, as nothing I do ever works.

Please if anybody has any answers or ideas please post them, as I've just had enough, I just want to live a normal life, work for a living and have a family one day. Thankyou in advance