Comebacks?

So here I sit on the fountain, waiting for the game to end, only one teammate communicated with plans, the other 3, just flaming and trolling, and opponents just snowballing killing 1v5 below 3rd tower. Any way to comeback, out of all the games I have played, I either win ez pz, or lose 50-1, Any ideas to this new player? Dota, HoN, and Smite are not like that, where one kill is an instant win for the team of that one kill.