How to win games when you don't have teammates.

85% of my games are the ones where I don't have a single teammate. They have all hard lost their lane, will not rotate, and will not get ahead even if i get them 4-5 kills by gank because they end up dying the moment ive not ganked them.

In these situatons, how can I ensure winning the game? how can i fight alone vs 5 people?