I think starting when the game was first released help me "level up" skill-wise with the community. Of course there were those worse or better than me, but there were also a lot of new players.
Now, the online community has died down, a lot of folks are playing/waiting for CS and it just isn't as lively as before. The majority of people you find online are seasoned vets at the game.
My first step of advice would be to pick a main character. Look at how pros play in videos, see what they do, see how they react, etc. Learn the most optimal BnB combos you can do. After this you can move on to more advanced combos (counter hit combos, character specifics, etc.)
If you need help with certain matchups you can read the threads here on DL for some advice.
Taking a break now and then is good, there's no point to get overly frustrated with the game. You can save your replays and see WHY you lost - that can be an important step. Watching yourself play again, you can look at the match critically - "Why did I use Hells Fang? Why did I continue the blockstring when I was getting punished for it? Could have RC'd to save myself " etc. Things like that. Learning to block properly, when to IB, barrier, and how to get out of pressure is also important, but that comes with experience.
Taking an extended break from the game can be detrimental to your skill. I didn't play in a few months and now I can barely pull off a TK mixup, CH hit confirm, or DP on the 1p side. So yeah, keep at it regularly, practice your combos in training mode a little if you feel rusty.
Just remember that CS comes out soon, and you may have to re-learn a lot of stuff when it does However, experience with the game itself will carry over.