My tuppence: I am going to assume there's a reason this person can't restrict their enjoyment of spicy food to home. For example, I would rather never eat a lobster in public again, as there are so many nooks and crannies and legs I want to delve into that I just... can't bring myself to do in a nice restaurant where I don't want to get my food all over my face. BUT my roommates keep kosher-style, so no lobsters at home for me, and in restaraunts I eat the tails and claws and a few nuggets but wistfully pass up sucking noisily on any appendages.

That said, I really think this person should make a little effort to not gorss out the people around them. Request a secluded table if at all possible, bring their own tissues and a receptacle for them, and take the used ones with them, and only dine with people who know about and understand their reaction to spicy food. I would put up with this for a close friend but I really wouldn't want to sit next table over from a stranger going through this while trying to eat my own dinner.

But honestly, if the LW were my friend, if at all possible I'd try to regularly cook spicy food for thm at their home or mine, because, ew.