Brain fog from toxic liver?

Hi all, just signed up hoping for some help and answers. Ok here's my tragic tale... When i was 22 i was invited to my cousin's 21st birthday, so i went along and had a few drinks. I only ever drank on special occasions. I had from what i can remember.. 5 pints of cider, 1 pint of lager and a long vodka. The day after i had the usual mental hangover symptoms (not feeling yourself, spaced out) though surprisingly no sickness or nausea, probably due to eating throughout the night. I had this feeling before, after drinking alcohol, but it usually went away after 3 days, but it didn't this time. I still have this brain fog and it's now been over 3 and a half years. I've been to the doctor, psychiatrist, psychologist, the gym, everything, but nothing has helped, well just maybe ruled out a few things. I thought it was my thyroids, thought i had depersonalization, but nope all fine. I even had all my Amalgam fillings removed because i thought/think it was the mercury leaching out from them into my body and brain.

But it's got me thinking lately, what if it was my gut/liver? This literally happened overnight and i haven't been the same since that night out drinking, and it's been a constant feeling ever since. It has ruined my life and i'm now at the end of my tether and don't know what to do anymore. The gut/brain connection seems the most plausible cause, what does everyone think, and recommend i do?

Thanks in advance.