Echoing everyone's sentiment, thanks to all for posting these responses. I've been following this thread myself for quite a while hoping for some miracle cure to be posted, but unfortunately nothing I've tried (and I've tried most) has really solved it.
My one, true, defining symptom is the incessant itch about an inch into my right nostril. It's always the right nostril, in the exact same spot every single time the itching flares up. When it starts, I'll sometimes take a pen cap (as it seems to be just the right length) and use the "arm" of the cap to lightly scratch the bullseye. I do this in an attempt to get relief for just a short amount of time. Scratch, sneeze, blow nose, repeat until I've desensitized the area enough where the annoyance is reduced to a more tolerable level for 15-20 minutes. Yes, I know this isn't a great idea as it can cause tissue damage, but it gets to the point where the itch is unbearable and I just need something to make it go away, even if it's only temporary.
I've had my itching symptom for years now. For me specifically, the eye watering and runny nose seems like just a secondary reaction to the itching, and I don't consider them my main symptoms. When I poke at the itchy spot, my eye waters like a faucet and my nose runs. Something is causing the itching, and the itching is causing the watering and running. Therefore, I feel like if I can stop my itching in that one dastardly spot, that all of my problems will go away.
I've been to an ENT. He looked inside and said I have a minor deviation, but not enough to cause problems. His response was the standard "oh, it's allergies", but I kept insisting that if it were allergies it shouldn't be in the exact same spot every time. I mean, I can touch it when I'm flaring up and make my entire face leak, for heaven's sake. He said that it's probably just an area in my nose that can "easily collect allergens" and thus my body reacts to allergies. As I'm sure most of you on this thread will agree, this is not the case. This is something physical.
Strangely enough, exercise does not seem to make my symptoms flare up. That seems to be a common occurrence in this thread. Yes, I've had itching occur after working out, but I do an intense workout 3-4 times a week and it isn't consistently triggered. Also regarding my lifestyle, I work in an office in Hartford, mostly sedentary for 9 hours a day during the work week. There isn't much to trigger an "allergy" attack here and even with the controlled climate, it happens here as much as anywhere else. I do have allergies (tested) to pets, pollen, and molds, but they aren't as intense as when I was a teenager anymore, and honestly I'm not even sure if half of my "allergy" attacks when I was a kid might have been due to this itchy spot.
Ibuprofen helps, but only in the slightest. I'm right-handed and it's my right nostril, so I just wanted to throw that out there as I know some people were talking about some potential relation to the opposite side of your dominant hand. I neti-pot multiple times a week, but only for the last year or so. It doesn't provide me much relief and I continue to do it just to keep my nasal passages clean.