Your Team Doesn't Matter
Whatever the success enjoyed or failures made by your allies does not matter. Whatever bearing their involvement has in any of your games does not matter. It really doesn't.
If you rely on allies to win or succeed 60%+ of the time for you then you are probably going to lose 50%+ of your games.
If you think your allies are responsible for 100% of your losses then you will probably never improve.
And if you let anyone on your team convince you that you are doing terribly and that there's nothing you can do to change it then you will only continue playing poorly.
This is a team game, BUT! you are only in control of and responsible for what you do. When it comes down to making decisions, focus on what you know, what you've learned, and your gut instinct whenever that voice in your head says, "this is a bad idea".
You have a brain, use it. Don't be sheep.
Be a person. Know who you are and learn what you can do. Own up to that. You want to succeed? Then plan for your own success, not the success of 4 other people you may or may not know.
Your team doesn't matter. You are what matters.