The whole issue is very complex, that's for sure. The extent to which these kinds of "illnesses" or "sensitivities", in myself or others, are "all in the mind" or "imaginary" is something I've considered and researched very heavily, and found it to be applicable to a significant degree.
But to someone who is in distress/pain/fatigue, the retort - whether from a doctor, a well-intentioned layperson or an insensitive asshole - that "it's all in your mind" or a "placebo/nocebo", is unhelpful and simplistic, particularly if you accept that the mind and body are all one entity anyway.
And then there is the reality, that you acknowledge, that certain effects are too subtle to be observed with current measurement technologies and diagnostic methods, inevitably leading to both false positives and false negatives.
In my case, the key to getting well has been to address all aspects, including diet, environment, and mind/emotions - the latter of which has had the most significant effect. Which puts me in a position to say "yes, in fact it probably really is the placebo effect, and I've used it to recover from having really terrible health to having great health", to which the next standard response from curmudgeonly skeptics is "the placebo effect doesn't actually change anything about your health, it only makes you feel better" - as if feeling well and being well are independent phenomena.
So, in my case you chuckle to yourself as you realise you're having an unwinnable argument with people who are more interested in feeling smart that achieving any good, and get on with doing what works for you.
As for the "femtocell", thanks for the tip, I hadn't heard of it. But really, as I said in the previous comment, EMF in my environment is really not an issue I worry about, I only take care to avoid having a transmitting phone right next to my head as I sleep - given that good sleep is the most critical factor in overcoming fatigue.
Many thanks for the discussion.