My girlfriend blamed herself for doing something wrong and felt unable to face me. What if you want to comfort her?

It is human nature to make mistakes, and not all mistakes are unforgivable. No matter what mistakes he made, what does it matter if two people are really happy together? Just tell her that if she really loves you, she will forget and let you start over. Tell her it's not unforgivable that you blame her. Give her a chance to make it up to you (so to speak, make her heart smaller), and then try not to mention it again in the future. If she insists on leaving anyway, then you.