Mustafi discussed the situation in a column with arsenal.com.
He said, "It gets a little bit frustrating to read those comments but at the end of the day, you have to be professional and I tried to be as professional as I can. Sometimes you read comments and you really disagree, and you want to say something but then you just leave it because you want to stay professional.
"The next day you've got training so you've just got to take all that energy and just use it on training and trying to improve yourself, rather than just on social media.
"One thing my wife said to me which helped me a lot was, 'You always have to remember where you come from and where you arrived now because it wasn't just luck. There was a lot of hard work, a lot of difficult decisions, a lot of sweat that brought you here. There's a reason why you're here at the moment so just keep going and doing what you know you can do'.
"And that's the main advice I have for anyone who's receiving criticism: to listen to those closest to you. They're always going to tell you the truth and if it's going good or bad, they're always going to be there for you."