All pve servers care about is achievements, they aren't the people you want to be learning from/playing with anyways. Transfer to a VERY populated server (not sure a good one for your region (i'm US) but should be easy enough to figure out). Once you're there don't immediately occupy yourself with playing with higher rated players. That will get you nowhere. Worry about your own personal play and do nothing but try to improve (if that's what you want).
If you want to become a solid player watch other high rated players and your play and positioning (streaming is easy to setup and you can watch your vids or just record locally to your hard drive)
Not blaming your teammates for losses, staying upbeat, and having this mindset will only make people want to continue playing with you:
"What could I have done differently?
If i was standing somewhere else or used a different cd would I still be alive or would we have gotten that kill?
What could I have communicated to my teammates as far as what I needed from them? (usually referring to cc, or their survival cds. ie: ring, life swap)
Was the target we were on not the correct choice? Should we try swapping more or to something different?
Stay positive and if you're on a losing streak just take a break go play some tetris, walk around, come back and joke around (you see me jump off that ledge like an idiot?

). it's pretty crucial to play with people you have FUN with, it's a game right?
There's tons of guides as far as what to be doing properly as far as positioning, cd usage, how to properly do damage, and keybind. All of which I recommend and should be easy enough to find. If not i'd be glad to help you find one. Good luck man!