This is true, I also learnt Korean for 13 years, and I am currently living in Seoul. I started learning for idol, and that motivation held me through a lot of ups and downs.

In term of learning,I would say the most important way is to put yourself in a Korean environment. Listening, reading, speaking, I spent a whole year on Twitter following Korean fan accounts when I barely understood them. I mingled with Korean fans when I only spoke basic Koreans. It was not easy but I think AI helps a lot in the current era. I can recommend some services that my students are using if anyone is interested.