I chose to ask this question here, as this site is full of language learners.
So, the problem is that I enjoy a lot about two languages, the other being Japanese and other being Korean. I love those languages a lot, but I don't have time or energy to study both, but it's really hard to choose. I usually end up doing other for sometime until I start to miss the other language and return to that and then after some time I return back to other. It's annoying as I loose progress because of the switch and I can't stick with the switch. What should I do?
I have tried to tell myself good sides of what opens with the language and Japan has clear advantages, as it's easier to pronounce for Finnish, I enjoy the media more and words stick easier than Korean words, but I still like Korean, a lot and it's too hard to drop it. What should I do? Should I just get stuck with this cycle or what?
I think you can learn both at the same time provided you stay disciplined in using the languages. You may not have time to study both languages every day, but you likely do have time to listen to music while doing something else. Let your brain hear the words to keep the ones you know fresh in your mind.
It takes very roughly a thousand hours of study to become fluent in a new language if you spend several hours a day studying it, and more hours if you spend less time per day. Splitting your time in two will probably more than double the time it takes to become fluent in both. You have to decide if the trade-off is worth it.
I would pick the language you are most passionate about and focus your time on that until you've reached the level of fluency you want. Commit to yourself that you will spend at least x many hours per week studying that language. When your mind needs a break, switch to the other language, but make sure you spend your committed hours with your primary language. I've seen vastly better results when I study every single day, even if only for half an hour.
It's hard to tell you an answer for your question i try. For me Japanese and Korean are really related (of course i can be wrong) so if you don't have time or energy to learn them both i suggest you to choose the one which is easier than you and learn it. After that you can start learn the second language.
How about learn both at the same time. That is just one suggestion.
When you are up to a particular subject in your language learning, learn that subject in both languages. Being able to compare and contrast the two might actually help you to remember more (they are distantly related in grammar, and both borrow some vocabulary from Chinese).