I would say trust yourself...Also, consider the possibility that the symptomatology or pain syndrome could be a hyper-manifestation of something emotional/psychological. There is a saying - nothing to fear, but fear itself...
Human metabolism likes sugar - that's why we have a taste for sweet things, and gluconeogenesis...Fruits complex glucose, fructose and sucrose. Honey is best as glucose/fructose.
Alternatively, in the context of a nutrient dense diet, there's refined sucrose in the form of refined cane sugar. Maybe you can experiment for a few days with raw honey or some kind of evaporated cane juice (rapadura) to identify if your problem is specifically with fruit.
Is the fruit organic and ripe? How about low-fructose fruits? How about fruit juices (without their fibre)?
I'm not saying these practices are optimal, although you may be able to try different things in the short term for experimentation/probing.
You do sound pretty sorry for yourself...In fact, who/what is the "self"? Maybe life is not actually as crushingly serious as you've been lead to believe...Maybe life is always playful and when you go with the flow, the flow goes with you...Maybe you're thinking in terms of limitation rather than having infinite freedom to experiment and make mistakes/successes...Life is awesome always, so be here now, snap out of the illusion of a fatigued mindset and say to yourself that you're not trying to get one up on the universe, you're simply here for some very interesting mischief, be that discovering healing strategies, realising that men in white coats only have limited tools for helping people (cut,burn,poison - oh, demoralise), womanising, fantasising, whatever.
Have you heard that saying: If you go to a psychologist, you ought to have your head examined...LOL!
Natural sugars are not your enemy...Natural sugars existed long before our species, especially when complexed with other substances in fruit/honey.
P.S. We live in a schizogenic society, so maintain your sanity by trusting your sensitive equipment and taking another human's rationalisations as non-serious. LOL...