When you’re bad mouthing your partner to friends who care about you, they only get one side of the story. They see all the faults in your partner and get mad at them along with you. They speculate about your partner’s intentions and make up stories that only add to your frustration.
It’s not fair to depict your partner so negatively to people who may know you both for a long time. You’re not giving them a chance to defend themselves.
And your loving friends will give you advice based on their jaded perspective. They’ll jump to terrible conclusions and often tell you to make rash decisions.