For me, it is not even physical stomach ache as you suggest, it is the mental aspect of total and complete brain derailment until you go eat something.
I guess I could ask someone to lock me in a room or something. That is not practical though as unlike smoking or drugs you need to eat something to stay alive - you cannot just go 100% cold turkey to try and break the addiction because you need to eat eventually.
That comparison with addiction to illicit drugs always perplexes me, because those drugs are clinically known to cause physical addiction to that substance, but that's not the case for (most?) food.
I do get the thing about it completely consuming your brain though (and being doubly painful if your stomach's in pain) even if it's a different phenomenon than drug addiction, so I'm not discounting that at all.
It sounds like this is something you've tried in the past. Have you given your body enough time to adjust when you've tried this? From what I know, when people start to fast (note I'm not suggesting you fast—just cut your portions > 50%), it's way more painful in the beginning (both physically and mentally) than it is, say, 2-3 weeks later. If you haven't tried this, do you think you could give yourself a chance and just tolerate it for (say) 3 weeks? I wonder if having a definite end date to look forward to might make it easier for yourself to convince your brain to tolerate some hunger?
If it was just a matter of waiting a few weeks then we'd not have an obesity epidemic in the west, nor would the huge huge huge dieting industry exist.
My main point is that people will give mechanical advice for losing weight, but it's very hard to tell someone what feelings they will go through. It's very hard to tell someone else what 'normal' should feel like for them.
Actually I was wanted to ask the opposite: what prevents you from letting yourself go hungry a fraction of the day? You might get a stomachache for a bit, I know, but have you tried and seen any consequences beyond that? Note I'm not suggesting "eat absolutely nothing the whole day", but like if you cut your portions into a half or a third of the usual (or eat fiber/etc. so as to at least fill your stomach)... is that going to actually cause you any problems beside a bit of stomach pain? (and might trying a mild pain reliever like acetaminophen potentially help with that until your body gets used to it?)