Promos 4 times, failed 4 times due to trolls/afk's/boosted players

I can understand maybe failing promos a couple times, but when I go on a 5 win streak and only need 1 more win get promoted yet lose both games because of people trolling in my series, it starts to get ridiculous. I seriously do not understand how every game will be perfect until I'm up for promotion. Is there some sort of system to match you with the worst players it can find at the time? Riot, this is serious bullshit. I honestly want to know WHY do my promotion games have to be worse than playing in bronze. And if the players in my games are not trolling, then how in the hell did they get past silver? So tired of all these boosted players ruining my games or people afk'ing because someone asked them to play safer. I'm almost ready to just say screw this game because it doesn't seem like anything is being done about people that intentionally ruin the game for others, because if anything was being done, I'd have gotten through my series by now rather than fail it 4 times in a row.