Another one here who is a "fussy" eater.
Where is the line between "fussy" and "don't like something"? Because, quite honestly, as an adult, I don't see why I should eat something if I really don't like it. I LOATHE cooked or melted cheese and the smell alone makes me heave. Eggs are the same. It's not a question of being "not keen", I really HATE quite a lot of foods - usually taste, but sometimes texture (fruit, for instance). If I like the taste of something but the texture is an issue, I have tried to make myself like something but trying it regularly but it just makes me gag. Which is unpleasant for other people when dining out.
My friends and family are aware of this and, bless them, they make allowances and occasionally will cook something separate for me from other people, just as I do if I am having people round for dinner and one has a nut allergy, or one is a vegetarian.
I have to say, I don't LIKE not liking a lot of foods. It limits where I can often go out to eat. At a wedding recently, I literally ate NOTHING off the menu (interestingly, there were eight on my table and three of us didn't touch a thing, so maybe I'm not so "fussy" after all).
My ex was vegetarian. We managed for 10 years. Sometimes we cooked for ourselves, sometimes we cooked for each other, sometimes we cooked something we could both have and just add in one other item.