So, if the community in generap scares you (honestly, do not blame you) you can aleays mute others as the match starts or right after they start bejng toxic if they decide to be toxic at all. I met a really nice thresh last night that I was up against in lane, had nice chat with them before going to bed. Not everyone is bad or will flame you, but for those who do I tend to just mute pretty quickly and go about my business enjoying the game.
As for smurfs. I wouldn't worry about them in the long run. Smurfs will usually end up where they belong fairly quickly due to MMR. You'll also benefit from smurfs on your team on occasion. But what will most likely happen is, they will not consistently stick around in your games unless you're climbing and are in the same skill bracket as yourself.
Regardless, I hipe you continue having fun with the game. If you do try PVP out again, don't beat yourself up over things that may have gone wrong or people being jerks. Try to learn and improve. Most importantly, enjoy yourself.