How to win the "1v5" type of games

Recently I've been dealing with a lot of games where every single lane is failing except for mine. I only fail mine when there is a Lee Sin camping my lane or something along those lines. As a mage player, I am not able to carry by myself, nor am I able to hold 4 fed carries on their team. Our Urgot rage quitting because he misses all of his abilities, diamond Thresh main unable to hit a single hook on the enemy, ADC not dealing any damage whatsoever. It's not fun and it's pretty much just wasting time at some point in the game, my team being aware of that but still not surrendering. What should I do to win in this kind of games?