I had an issue a few months back in which I had a load of spare time to invest in chess.
I trained viciously practically 8-10 hours a day. I got to a stage after about 3 weeks where I became so frustrated at my lack of progress in my game. I would look over games and be very angry with myself for stupid mistakes I would overlook while playing.
I managed to reach roughly 1900 in local tournaments, and yet that was not enough to help me enjoy the game.
I am rambling a bit here, but in a nutshell don't train to hard or take it too seriously or you could end up in my position where it becomes hard to enjoy the game.
My Grandfather used to teach me when I was little. he had a rating of 2200ish and would train me for about 7-8 hours a week. I felt this was a good balance.
Whatever you do, try not to loose your passion.
I have been passionate about chess since childhood, however, never having the right opportunities or guidance to make sustained progress. At this point of time, I am hoping to have a personal improvement plan which sorts of rigorously tells me how to do things to improve my game and hence rating.
The motivation for seeking this is simple.. without it I get lost after a while and it affects my passion for the game.