Help me understand what I'm doing wrong.

Hello guys.

Here's the deal. My name is TheEmbermage and currently I'm trying to climb, as I have some free time. Last season was great for me, if I'm not wrong, got to Gold 2 with around 56% winrate. That's where today brings us. I got placed at Silver 1. Went down to SIlver 3 in 2 days, I managed to climb to Silver 2. I'm at around 30% winrate. I usually win the lane, or keep it even (90% of the time). That's where others come to play. No matter what I say or do, some lane keeps losing (2 most of the time) and we lose. Badly. I ward, I try to play off their mistakes, I can't do anything later in the game, when we're usually 3v5, or people blindly run into the bushes.

I'm not trying to flame but I ask you for an advice - -how can I better myself to stop relying on my team and carry myself to Gold again?

Thank you for your responses. Cheers!