I wud try n stick to a red day n eat a steak n ask for a salad instead of chips or potatoes, if they don't have steak on a 2 for 1, maybe something meaty with say lots of veg or salad, it's hard but so long as u don't have tons of creamy sauce or dressings u shud be able to enjoy!
I am going out for a meal for our anniversary n my hubby is panicking but u just ask for something to replace something in restaurants n hope they can accommodate u x
Enjoy x