Relax, everyone feeds, it's hypocritical to get mad at someone for having a bad game and making mistakes. Everyone has had games where they have played bad and were the cause of their loss, and in those games the others call you the feeder. You might get a feeder and lose 10 games in a row, but each of those feeders was likely a different player, and those 10 players all had carried and won their previous 9 games. So, you would just be unlucky. Relax and just move on to the next game, focusing only on your mistakes. Telling someone to go afk isn't a good solution, and telling them that will likely just make them play worse. Try to be a leader, try to watch the minimap and help keep your team aware, if you're the better player and make few mistakes then guide your team and keep a positive attitude.
I'm sure everyone has had a 0-5 game and was called a feeder and/or told to afk, and I'm sure it didn't make anyone play better for the rest of the game, so you should understand that sometimes it happens.