My girlfriend of three months has a 13-year-old daughter who has a tantrum if she doesn’t get her way and pressures her mom until she gives in. Last weekend, my girlfriend and I were making dinner when her daughter demanded to be taken to a friend’s home. My girlfriend refused. Her daughter began screaming and knocked over a plate of bread on the counter. My girlfriend called her a bitch, and she was right. My girlfriend tried to continue cooking, but her daughter kept yelling. We just wanted a nice evening, so she drove her daughter where she wanted to go. Later, I told my girlfriend that she should call the cops to teach her daughter a lesson. I can see myself with this woman long-term, but how can I help straighten this kid out?

S-L-O-W-L-Y. Your girlfriend lacks even the most basic parenting skills and requires advanced skills immediately. The only way you can help is by holding up a mirror so she can see herself clearly. And don’t take your girlfriend’s side against her daughter. Unless this teen has been diagnosed by a psychiatrist with something like bipolar disorder or oppositional defiant disorder, you can be certain the problem stems, in great part, from the way she has been raised.

Rather than blaming her daughter, your girlfriend should take responsibility for her own weaknesses. Name-calling is one. When an adult curses at a child, they are announcing an inability to manage their own mind or emotions. How would a child learn how to handle uncomfortable thoughts or feelings if this behavior has not been modeled at home? Ah, yes, now you understand the real problem.

Here’s another simple insight: Your girlfriend does not want to be a parent. She likes being your love interest and wanted her daughter to go away so she could continue in that role. That’s why she responded with a quick “no” without listening to her daughter. I bet that, prior to the drama, that child was sitting in her room, angry at the loss of her mother (yes, to you), uncomfortable with the intimacy between you and her mother, and wishing she was anywhere else. By the time she figured out what to do (leave), she was so angry that she didn’t make a request, she demanded an exit ticket. Given the circumstances, can you blame her?

Your girlfriend also failed Parenting 101 when she gave into her daughter’s demand to be driven to a friend’s home after saying no. By saying one thing and doing another, your girlfriend undermined her own authority; her daughter became head of household. I doubt that it was the first time, either. So here’s a primer: No means no, yes means yes and maybe means maybe.

Parenting is a lifestyle choice that demands selflessness. You must be able to put the needs of your child before your own, especially as a single parent. When your girlfriend heard her daughter’s request, she should have responded with love: “Hi, honey. We’re making dinner right now. Let me turn down the stove so I can talk with you.” Your girlfriend also should have asked the preliminary questions needed for decision making, like: “Are you feeling OK, sweetie?” “Can we talk about your plans?” “Here’s what I need to know: Will there be adult supervision?” “What do you plan to do when you get there?” “Do you need a ride home, or will [name of friend]’s mom or dad be dropping you back here?”

These questions reveal a parent’s loving concern. You can show your love, too, by not participating in family life until your girlfriend has learned to parent her daughter. And that includes not making any more crazy suggestions about calling law enforcement in to do the job for her.