You have found omega 3

"However, I also note that, the best I ever feel, is when I take 40 grams of fish pills a day. Can you imagine that much?"

I think that you've found a major part of the solution to your problem.  In the book "The Omega-3 Connection" (2001) by Andrew L. Stoll, MD, Director of a psychopharmacology research lab and professor at Harvard, they treat "psychosomatic" difficulties with omega 3 in the form of fish oil.  They use significant amounts of it for various conditions with great benefits.  From the book:

"If you are using the omega-3 fatty acids for health, mood, or cognitive enhancement, 1 to 2 grams (1000-2000 milligrams) daily of total omega-3 fatty acids (EPA plus DHA) is probably adequate.  If you are using them for mood elevation or stabilization, a higher amount is sometimes required.  Our bipolar disorder study, described in Chapter 7, used 9.6 grams of omega-3 fatty acids per day (6.2 grams EPA and 3.4 grams DHA).  Clinically, usually 2 to 3 grams of omega-3 per day is adequate."

I think you would find that book a good read.  The doctor recommends fish oil over flax oil and that's my preference because fish oil has a one to one ratio of omega 6 to omega 3.  The native diet of the Inuit has a ratio of of one to one - the current typical American diet is over 21 to 1.  The Inuit are virtually cancer and heart problem free. 

I've been taking a lot of fish oil lately trying to get some my cholesterol down and that seems to be working.  I get Costco's fish oil which is by far the cheapest and is claimed to be from deep water fish (not farm raised) with PCB's removed and extremely low chances of mercury (.1 part per million).  The Costco oil is 1000 mg of fish oil with 300 mg of omega 3 fatty acids.

I still recommend meditation too because there are sooo many "psychosomatic" difficulties that simply disappear.  You can also get in touch/communication with your body and respond to its needs much easier than without meditation.