You're quite right. This is NOT an issue of imsomnia v snoring at all.
I do NOT suffer from imsomnia but I have laid awake, sometimes until 5am or later, because unfortunately my partner also snores terribly (no matter how he lies) and he grinds his teeth, and he talks in his sleep, so really, I have no chance.
Like you, I don't want to take sleeping tablets because I want to be aware enough to wake up if my young child cries out - and I doubt very much a doctor would prescribe sleeping tablets on the basis of drowning out someone else's snoring. Besides, when they are prescribed, they are usually a short term measure - these days no doctor will usually hand out sleeping tablets as a ongoing solution.
My partner has tried all the over the counter snoring remedies - sprays, nose strips, strips which melt on your tongue, a mail order gum shield thingy etc. None of them have helped. I think the next stage should be that he goes to the doctor to check if there is an underlying condition contributing to all the noise he makes when he's asleep, but despite visits for other reasons, he somehow always manages to "forget". I suspect this is because he knows that the doctor will first of all tell him that he should stop smoking, and secondly, he should lose some weight, before they investigate anything else.
Anyway .......... he ends up sleeping in the spare room most of the time. Previously, when we had a smaller place, he went on the couch. I know that's not ideal, but he's the sort of person who can sleep anywhere (he says so himself) and what else can you do if one person is being continually sleep deprived ? I used to feel bad about it, but now I feel that he hasn't done all he could do to help himself, i.e. go to the doctors, so in some respects, he has to lump it - though obviously, I would prefer him to at least try and get it sorted so we can sleep together properly again.
BTW, I have tried various earplugs - both sponge and wax types and they do NOT eradicate enough sound for me to sleep.
In your case, he does sound terribly selfish. He's twisting things around to suggest that this is your problem (something my DP has never done) which is plainly ridiculous. Even if you had no sleep problems yourself, any loud noise just 2 feet away would keep most people awake. If he cared about you, he too should willingly offer to sleep on the couch if he starts snoring and, at the same time, be trying all possible remedies, and being prepared to go to the doctors if all else fails.
The bad breath and farting confirms he's very selfish and he's basically not showing you much respect in your own home.