FF@20 in Series!

I clicked no, we had not yet even lost an inhibitor turret and they ff'd. I only had one death FFS! Maybe the game didn't mean shit to them, but are you fucking serious??? There is absolutely no argument, my team LITERALLY lost me my series, and set me back 3 games all because they couldn't wait 5 extra minutes to see how the game was gonna go. Why the hell can my teammates force me to lose my series beyond just feeding, but literally snatching the LP out of my hand? What kind of system is this shit??? It's bad enough they fed but DAMN, did I mention I had one fucking DEATH???!!!