I'm going to be very blunt. However my knowledge comes from observing other people, not direct experience (yet) in my own publishing saga. And so feel free to ignore me. My complete talking out of my ass in fact is a very safe space for you to be in right now, because you can think I'm idiotically naive and not be troubled further.
Here's the thing: Publishing is not a lottery. YES, some good books don't get published. And YES some bad books do... However, this REALLY is not like your name getting pulled out of a hat, or your raffle ticket drawn. There are things you can do to increase your odds exponentially. Studying the business intensely is one. Surrounding yourself with successful people is another. Reading and writing as much as you possibly can is another. (I mentioned in another blog entitled: "But mine is different..." that a short query and not too much set up in the first chapter of your novel will put you miles ahead of a lot of the competition.)
THE odds in general are not the same as YOUR personal odds. Don't make the mistake of confusing the two. Don't get me wrong, I'm not talking "delusions of grandeur" here. I'm saying, someone else's personal success or failure in no way has anything to do with you or what you can or cannot accomplish.
Whatever you can do to improve your craft, do it. If you fail, it might not be your fault. But it might be. Take responsibility for your own faults, whatever they might be. I am in no way, shape or form implying that any one individual person is wholly responsible for their failures, I'm saying, on the whole to grow, you must own up to whatever you have done that is self-defeating.
Over and over I've seen people who have "made it" have very similar attitudes. Maybe you believe they have those attitudes because they've succeeded, but I believe those attitudes are partially responsible for their success. I'm not just talking about writing, I'm talking ALL areas of life. Most people I've ever met who have ever succeeded in any area of life had a winning attitude to match. If you don't have the attitude, get it.
You have GOT to believe in yourself. Absolutely, above all else without reservation. There are many roads here. You don't have to take any given one, but get on a road and go somewhere. Don't bitch about "the industry" as if it's personally out to get you.
Figure out what you have to do to get where you want to go and start moving. Stop bitching. The world hasn't promised you anything. You aren't automatically entitled to anything. You have to make it happen. You have to know you ARE the magic.
Attitude and talk alone won't get you there. The power of positive thinking can't be what completely steers your ship. You have to have a plan and you have to work it. But please, for the love of God and all that is holy and unholy, don't allow yourself to fall into the traps of self-defeat. Just refuse to do it.
You might put all your hopes on one dream. You might try and strive and be good and have a great attitude and not make it. (If we are talking odds and you do ALL these things and don't just lie to yourself about it, those odds aren't nearly as great.) But so what? Your entire identity and self worth cannot rest on the success or failure of one dream. Even if you fail, you have to believe it's worth the attempt. If you don't believe that, then yes, your odds suck.