If 'always,' 'forever,' and 'constantly' are used in a continuous tense, it means something happens more often than normal. For example:
She is always forgetting her keys ( - she usually forgets her keys, and it is not good.)
Therefore, I guess the meaning of the given sentence is 'I started studying Japanese a long time ago, and I am still learning it. Surprisingly, I will continue to do so.'
So, it implies 'he/she loves studying Japanese until the end of your life, or he/she not intelligent enough to learn in a limited time.