"They (the media) can say what they want...they will not bring me down, I'm stronger than that," the France defender told French sports daily L'Equipe on Friday.
Gallas was criticised for his behaviour in a 2-2 draw at Birmingham City in February, when he walked away from his team mates and stood in the other half of the pitch after the home side were awarded a stoppage-time penalty.
"It makes me mad because I don't think (what happened in Birmingham) was our problem," he added. "How can you summarise our season with that thing at Birmingham? That is not why we stopped winning matches."