I mean, trying to maintain several languages you're already fluent in is not easy:P Especially when you're trying to learn new languages too, and when you have to devote time to that language, your level in other languages sometimes plummets:P
I havent been good at English yet, but I have started learning Korean for 3 days. I have to arrange my time to maintain my English and have time to study Korean. I dont to practice and use them daily now, but I going to change my job and they will be needed for my work. I just try, and yes, it is hard as u said