My girlfriend gradually ignored me after she worked. Every time I ask her where she is, she doesn't say anything. She heard from her best friend that her boss often takes her out with her friends.

First of all, she definitely doesn't want to break up. It can be concluded from her best friend's words that she thinks you were a little cold to her before, no matter what happened before, even if you think you did the right thing. Apologize to her directly, express your position (for example, you don't want to break up, love her very much, and hope to make up), and talk about the beautiful things between you. A woman's heart is a needle in the sea. Try to make her understand you when you don't understand her heart.