I'm not a great player like some on here...so the actual answering of your question I'll have to leave to the more experienced here. What I would like to say though is it's quite likely you've improved far more than you realize. Learning basic tactics is in essence trying to stamp out the blunders. Trying to think 1-3 moves ahead and avoiding traps. With each game you lose at this point you're learning what NOT to do. Most people (myself included) will NEVER get past this point. Try as we might there's always the occassional goof that will cost us dearly against a truly good, or great player.
In my opinion, getting past this stage depends far, far more on actual experience with pushing the wood than study, which likely plays a greater role as your game becomes more consistent and blunder free. You say that you still lose to 1000 players...let me ask you this...Is it the same exact mistake over and over again? Likely it's not. Only a true idiot (and I don't think you are) makes the same error time after time and expects different results. So...what is happening? You're learning...slowly, painfully, but you're learning.
Yes, I know you've said you're competitive and I understand the frustration that comes with realizing you're not a "natural grandmaster". Unfortunately that's not the fate the universe had for you (or me)...instead you're just 'normal'. And that means if you really want to improve your game you're going to have work damn hard at it, for a very long time...and even then you may never become great. But you will improve as long as you keep at it, and keep learning. Inch by inch, blunder by blunder you'll keep going forward. And then one day you'll look back and realize something...that you're already better than the vast majority of players and you got there without even realizing it was happening.
I am just now starting to improve a little bit and have a long way to go but besides the obvious study of tactics, endgames and some openings, I think the best way to improve is to get a coach.
I can only get a lesson with my coach once in awhile but they are always fruitful! He goes over my games AFTER I have analyzed them myself, that way I can get more out of his critiques.
I have a long way to go but I am seeing improvement.