You learn more when you lose, than when you will. Calling 'trolls' won't make you better. You have to examine the match. Sometimes you can win by going for towers in a 4v5 situation.
Just won a 21 lp match (in gold II division) in a 4v5 scenario. We got 3 early towers - 2 on mid, 1 on top and they simply couldn't recover (maybe they were bad). We pushed hard when we could, and we backed off when they wanted to teamfight us 4v5. They ended up surrendering after our guy reconnected and we aced them 5v5.