When I started playing ranked in season 2, I was below 900 elo. Let me tell you, back then when you started ranked games, you were placed at 1200 elo in your first game. From there, you won or lost your games and your elo adjusted until you finished your placements and got to see your actual number.
It took me until the very end of the season to get within a game of where I started (1200 elo.) That damage to your psyche as a player, it's immense. I had spent hundreds of ranked games playing my very best, and I had yet to even achieve back to the place I had started when I played my very first game. Many times during those months I bitterly thought how different things would have been if I had just been able to win one, lose one, over and over, until ending with even win-loss or even just 6-5. Then at least I wouldn't have to be ashamed of being one of those players set in the water at 1200 elo only to sink to the depths.
However, like you, I realized that it would be a lie! If I had been fortunate, had gone 6-5 and ended at 1210 or 1215 elo, I would be no better or different a player than (the truthful rank I ended with) 900 elo. Instead, I focused on becoming a better player, like you've realized now. Put the numbers out of your head of your rank, your win/loss, your LP. Don't even think about your gains/losses, even if you are getting +8 and losing 35.
Focus on the fundamentals. Right now you're being told that you are a most basic player. You're at 0 points in Bronze V. This means you need to treat your experience the same way as the system is telling you: go into custom games. Practice last hitting. Practice with items and masteries and even spells, just trying to get those last hits. Do it by yourself in a game, for 10 minutes. Repeat. Do this until you're able to achieve more than 6.5 cs per minute (65 at 10 minutes.) Then do it with masteries and items but no spells, period, only auto attacks. Continue on this path, there are many other extensive resources you can easily find to train this, until you are satisfied with your last hitting, that you can do it automatically and without thinking, even against an opponent. Already this makes you better than the average Bronze player, but don't think like that.
Move on to the next step: start to intelligently question why you do what you do. Why do you play the champions you play? Is it because you've seen other people play them? Are they meta picks? Is it that one champion you got owned by when someone else used it? Determine what kind of player you are and explore. Use free-week champions and read up on strategy guides for champions. Find some that you are comfortable playing, that fit your style. Then start to question what to do with them. What do you build? Why do you build it? Are you taking a square cookie cutter and trying to make circular cookies with it? Learn to adapt your builds (and even spell orders!) to what other people are doing.
Throughout all of this, as you achieve deeper understandings of strategy and decision making, and refine your mechanical ability, you'll start to see more and more wins. Just remember, as it was when you were at your lowest, so it is when you're playing your best. Stop thinking about your rank, your LP, your position on the ladder. Before I accepted that I just had to get better, at everything, I was an impassioned believer in "Elo Hell" and was convinced that if someone just gave me a chance, I could be 1500 elo. That there was no real difference between me and a player like that. I even wrote a treatise on the concept and tried to convince others of the same. By season 3, I was Gold. Now I'm Diamond. It wasn't a simple 1, 2, 3 step plan. It was sitting right where you are now, after tanking my elo to a place I didn't think I'd ever even recover to where I started, and realizing that the numbers didn't matter. They were just showing me a truth I didn't like to accept: that I was a sub-900 player. If I wanted those to change then I needed the fundamental situation to change; I needed to stop being a sub-900 player and the only way to do that is to consciously work on, not increasing your rank but, getting better.