*Disclaimer!* I am NOT a pharmacist (the actual profession that studies drugs and their interactions) and anything I say that is misconstrued as medical advice is all on you!* 😉
That said, my father was one of the first to be put on Gabapentin (aka Neurontin) when it was first being tried for other reasons back in the 1990's (my father had a complex case of temporal lobe epilepsy and manic depression). It was during this time that my mother underwent major cancer surgery and massive chemotherapy (she was one of only two people to survive the level and type of cancer she had for that year throughout the entire United States). However, all that chemo torched her nerve endings and my father's doctor couldn't stop extolling the virtues of Gabapentin to aid neuropathy. At the time, there were no reports of any negative side-effects, so she ended up on the maximum dose (seven pills a day) for 20 years! So, as part of trying to get all of her meds reduced about two years ago (she's 91 now), I read a lot of studies and reports, including several on Gabapentin.
So, here's the upshot: Compared to the vast majority of drugs out there, Gabapentin is still one of the most useful and safest. The dementia issues all occurred in patients who took large dosages over long periods of time and, as my mother is evidence to, it still doesn't affect everyone. From everything I've heard and read, it really works great for neuropathy, but the key is to slowly reduce the dosage as the nerve endings repair.
My suggestion to you is to try and find the reports and keep questioning your doctors. It might help you in the short term!
Side-note: My mom is now in long term care as of late last month after a few E.R. visits, a hospital stay and a lot of attempted rehab starting in early November. One upshot of this is that they've removed a lot of grains and sugar from her diet and she just dropped below the supposed diabetic line for the first time in decades. She's never been far above, but she also wouldn't stop eating cheap waffles with pure sugar syrup for breakfast everyday either!
Remember, there isn't much of anything with your body that YOU can't fix! Let's just say I have far less respect for medical doctors than I used to and a lot of evidence (including personal) about what's really possible. Good luck! 🙂👍