Advice needed

Ok, so I just lost my 2nd placement, this was a game where our midlane morg kept chasing into baits, after we told her not to chase and to play safe, (I was even using my tp from top to stop ganks, she still continued to chase, and after and amazing early game, the enemy vel' koz started to get fed, and we were unable to touch him due to their tanky comp, but in addition, the enemy support would give morg a kill after 4-5 deaths to reset her gold value, how am I supposed to carry myself in ranked when I get put with people who just dont give 2 fucks about playing safe?