Stuck in silver, constantly losing games, lost 13/17 games the last few days? I used to be plat, top frag an awful lot...just don't get it. Any ideas?

I told my team I would be demoted if I lost, I knew instantly I made the wrong decision, I played with a three stack who threw five matches in a row on purpose, and a raze that threw her grenade at me every single round of the match just so...