Were you ever banned from CS:GO, if yes, why ?

Heh, for the annoying teammates part, I can relate.

I've once been banned for an entire week because I had a game with a young Spanish kid who laughed and said insults about me in Spanish whenever I was killed.
He gave me a false callout ingame, and from there I got angry to a point where I was going to blow up IRL. I screamed at him so loud all the rage and frustration got out of my body, he never talked again in that game. I decided to take a break from this game and teamkilled him at the end.

Yeah appart from that it's because of hacks.