I need a tip regarding incommunicative teammates

Recently in all the ranks games im having it seems that my team is ALWAYS looking for skirmishes, not pushing lanes ,not getting towers or objectives, not focusing on their CS, just making sure they ALWAYS fight the enemy team. Now if i help them, there is the big chance that my team gets earsed and then the other team will take towers and start pushing the hell out of us. because we are dead (obviously). And if i choose not to help, and push a lane so we can actually have progression towards destroying the nexus and therefore winning, my team wouldnt think "hey maybe we shouldnt start a skirmish, because not everybody are willing to in the team", no, they would just fight the other team without me, they will lose the skirmish and will blame me.

What is the best decision in such situations? i need a tip.