Are you sure your symptoms aren't the result of a food intolerance? I know a friend of mine who has Celiac's disease said that when he symptoms first started, they were really vague and odd (feeling light headed and warm after eating and some other non-GI symptoms). She did eventually develop GI symptoms and her diagnosis was then confirmed via testing. She said that once she removed all the gluten from her diet, all her odd symptoms (both GI-related and non-GI related) went away.
It may be that you're having symptoms following eating which you're associating with a spike in BGs. It just doesn't make sense that a BG of 100 would cause what you're experiencing. Also, the longer someone is T1, the more insensitive they generally get to swings in BG. Also, what you're reporting (subtle differences in how you feel depending on whether you're 90 or 100) doesn't make sense given the huge margin of error with home meters. Your meter may say 100, but you could actually be anywhere between 80 and 120 at that moment.
A few thoughts:
- Is it possible for you to get a CGM? If you can't afford one, perhaps your endo can loan you one for a week or two. It may be that you're experiencing bigger swings than you're identifying with a home meter. A CGM will pick this up. This has happened to me before; I would have symptoms of a low, but my meter would say 110 (or something equally ok). Turned out, it was because I was dropping from like 300, but I wasn't detecting the 300. A pump helped me solve this problem.
- Have you tried eliminating certain foods or been tested for food allergies/sensitivity?
- What long-acting insulin are you using? I thought you had once mentioned you used NPH; this will cause some folks to have HUGE dips and drops (and possibly subsequent spikes) which again you may not be detecting with a home meter. Have you tried other long-acting insulins?
- Is it possible that you have some autonomic neuropathy? I know from talking with others that auto. neropathy can cause some really weird symptoms.
- Have you had your thyroid checked? T1s are an increased risk for developing hashimoto's thyroiditis. From what I understand, this can also cause some strange symptoms (although you'd likely also be experiencing weight gain and fatigue).
You seem really bothered by what you're experiencing and I feel bad that you feel so bad. If I were you, I'd be seriously working with my endo and any other doctor to run tests and try to get to the bottom of what is going on.
Have you tried taking any medications to alleviate your symptoms? Sometimes, SRIs (like prozac and other medications in that class) can alleviate symptoms like the ones you're experiencing. For example, women going through menopause will sometimes develop some really bizarre symptoms because of the hormonal fluctuations and find relief in SRIs. You may have to experiment to find one that works for you, but if you're that bothered by what you're experiencing, it might be worth it.