How do you get back into the game after a while?

I stopped playing around Sombra's release. Everytime I come back, I just get utterly shat on or have toxic teammates, and I especially dont understand the current Meta. So everytime I try to play, I get people yelling that I'm playing the wrong hero, or I don't realize that my favorite hero was nerfed into the dirt, etc etc. If anyone has tips for returning players, I'm all ears.