Fell from Silver 2, to Silver 3, 59 lp?

I am not here to talk like low division guy (bronze) how my team is "bad", how i am "pro"... I just want to discuss about something. See, how is it possible for me to almost always get really good KDA, be in TEAMFIGHTS, PROTECT, WARD, BREAK TOWERS, COMMUNICATE.... And then lose the game? I play almost always as support, it's my main role. Last game, i tried carrying with Leona, went pretty well, considering we had 2:13 Azir, 6:10 Twitch and 2:7 Malphite i think. Even though they were making huge mistakes, feeding... I was positive and i wanted to cooperate with them. Zed was fed, with 2 quadra kills, so i tried staying positive and focused him and adc. I didn't rage, i didn't do anything wrong. I told my team: "Wait for Azir to come". Pinged 4 times, said again. But no, Twitch is going solo in jungle, Malphite is following him. So, since Azir was pretty much behind me, i tried helping adc because backing off would kill my teammates so quickly, so i tried helping them, but i couldn't, since Zed was overfed. And enemies killed them pretty easily. Now, that's the point. I am just sick of trying to teach someone how to play this game, but they won't even use their minds to see their mistakes and to think about their next move.Do you must have huge brain to understand we need to wait fifth player to come so we can def and maybe answer to their move? Like, they don't understand that every kill they give to them, they will be stronger and have plus 1% more chances to win. I wasn't angry when we lost, they didn't deserve to win, that's all. But that;s the point, you can't carry someone that theoretically IS YOUR TEAM, but like it's not. No communication. No one listens.