Mmm, ethiopian. Love it.
Unfortunately, I think the bread (injera) is actually fairly high in calories, and you generally end up eating quite a bit of it since there's no other way to eat your food. Also, if you haven't had it before, you're probably going to want to get the "vegetarian combo", which is usually like 9 different little scoops of each veggie entree. If you have had it before, you can get away with a single order of your favorite, which is much easier to control.
Is this a really special occasion? Like, you won't get to go out on another date with him for months because it's so hard to get a sitter? Or is this the kind of thing that might come up every week?
If I knew that this was going to be a really special night with my husband, then I'd have a light breakfast and lunch, try to burn at least 500 calories running or walking, and then just write down dinner and popcorn as 1,750 calories and move on. If this is the kind of thing you think you'll run into regularly, then I'd still have a light breakfast and lunch, still work out, skip the popcorn (bring grapes or something else instead), try to keep myself to one piece of injera (might have to ask for a fork), and one reasonable entree (like, maybe not the butter steak).
Good luck! It's not easy finding balance with all this stuff, but it's worth it!
