My fiancée does not know how to order off a menu. Actually she does, she doesn’t care to order from a menu like most people do.
Going out to eat with her is pretty much an hour long ordeal of me gritting my teeth while she racks up a bill 3x mine, all while trying nicely to steer her to just one item. She’ll open the menu, get overwhelmed with options, and end up ordering a la carte from places that do not work that way, asking for endless substitutions and upcharges. As an example, at a restaraunt, she might not be able to decide between a burger or chicken tenders, so she’ll ask for “a half order” of both of them, then she likes the sound of one specific dipping sauce that comes with another entree so she’ll ask for a cup of that, etc. Etc. I’ll say something before we go in, she’ll promise me she’ll just get a water, and then get a water - and a margarita. It’s draining. At this point, we go out maybe once pr twice a year unless something forces us out more than that.
The scenario that prompted this rant was that tonight was one of those times. Our bill was $82.10. My entree plus water was $10.99.
Maybe it would help if you had a heart-to-heart about why this is bothering you and (together) make a plan to tackle this. From your description, it seems like the occasional margarita is not really the issue but it’s the inconvenience to the staff, the embarrassment to you, and the costs that come with the dishes she orders. It might help to look at the menu online beforehand and decide on what you’re getting in advance. You could even pick out two dishes together, and you could share a few bites, if you’re okay with that. Her behavior seems to be at least a little compulsive, which is hard to get rid of but can be overcome with some practice.