After reading the previous replies, I have to say my initial post has changed drastically. I was going to say, "Just follow your heart." But now I realize there's more to it than that. People can follow their heart and end up in ditches, after all.
When I started learning Japanese, I was motivated by a sudden sense that I just needed to become fluent in it. So I started studying every which way I could, but I realized that I was never going to gain fluency unless I immersed myself in it. I enrolled into a Japanese language school based in Shinjuku, Tokyo, Japan. Studying in Japan for a year in a half really helping me absorb the language.
French, on the other hand, has not been that easy. While I love French and took 4 years of it in high school, practiced with my mother and grandmother (both having rudimentary understanding of the language), not having the ability to use it in every day life really took its toll on the learning process. While I'm passionate about French and love France, its culture, and the people, French has been infinitely more harder for me to learn. Even in pronunciation -- and people tell me I can pronounce anything.
In that way, I believe that while wanting to learn a language is the most important step, what really matters is how often you can use it and develop it from the inside out. Gaining a level of confidence with the language you're studying is crucial too. The best way for that to happen is to use it, as Saholy stated in their post.