The community definitely has its toxic players, but that's the same with almost any online gaming community. If you were to check on things like Dota, World of Tanks, etc, there are plenty of people that take delight in making someone else feel miserable while puffing up their own ego. And the sad thing is, thanks to the human condition, there isn't alot that you can do.
Fortunately, not everyone in the community is like that. There are plenty of people just like you and who will gladly treat you with respect. Furthermore, it's excellent that Riot has the tribunal system in place to deal with toxic players. It may not be a perfect system, but it is definitely better than not having one at all.
TLDR;
Just know that not everyone is out to get you; there are plenty of friendly people to play with or against.
Riot is working day and night to make this a better environment for everyone.
And remember, the mute button is your friend on many occasions. It is there for a reason.
Have fun and Good Luck
PS
SHOULD DIE!!!