10 Failed Series Attemps

I've now failed my 10th attempt at getting into Silver 1. I always win at least one game, lost two, then get dropped to about 80 MMR, ALWAYS win the next two and then fail my series again. This is legitimately the most frustrated I've ever been in my life. Any advice? I main Top/Jungle/Support and it seems as if 50% of my series games always have a DC in them, who's always on my team (Literally always, not figuratively). Any advice?