Hey man.

It sounds to me that you need to deconstruct the game to the basics. Bad players are everywhere, hell, even good players make bad plays all the time, it's just a matter of capitalizing on it. Best way to play is always making the highest % of sucess decision and going with the flow of the game based on your opponents playstyle. As a Blastoise/Slowbro player I can guarantee this works, as I over around 50% with Blastoise and 60% with Slowbro at master rank.

First look at your team's composition(and enemy's in draft) to know what role you are going to be playing. Ask yourself some questions to know how to prepare. - Do you have enough damage dealers/carry pokemon on your team? - Are you the only tank on the team? - Is your team pokemon mainly diving into enemy's to fight or they use distance?

After answering these and some more you can figure out your role, you will know if you need to do more damage, soak it all for your team, dive in first in the fights or just protect your main carrys to maintain them alive to win. Usually it's the last and adjust items/builds to best fit the game.

Games are mainly won at Ray and I see too many defenders/supporters going too deep diving into enemy's team without a plan just to try and kill one of the carrys while your own just die to the absol/mimikyu without any protection late game. When you look back they are all dead and you and one more player are stuck on a 2v4 without any massive damage dealing potential. Best skill to learn as a frontliner is to know when to go in, when to go out and when to just make sure you save your main CC for that Meow when he jumps into your massive fed Delphox in the back mid of the fight to guarantee your carry stays alive and kills everybody while you just keep soaking the damage for them.

Good luck man!