DEAR ABBY: My girlfriend of five years has a 28-year-old daughter, “Courtney,” who hasn’t liked me since day one. She never tried to get to know me and was rude and disrespectful from the start. Her mom ignored it and did nothing.

We have reached the point where we want to get married, and Courtney says we won’t be invited to share holidays with her, and she will never come to visit us. In fact, whenever Courtney calls her mom, if I am nearby, she hangs up on her mom.

Her mom has now broken out with psoriasis and is losing hair from the stress. She’s afraid of losing her daughter and is ready to end our relationship.

I told my girlfriend her relationship with Courtney is toxic and she needs to step back until Courtney is willing to go to therapy and make amends. With the exception of the issues created by her daughter, we have an amazing relationship — a love neither of us has ever experienced before. What should I do? — ROADBLOCK IN FLORIDA

DEAR ROADBLOCK: As long as Courtney is allowed to dictate how her mother lives her life, you two won’t have a successful marriage. Unfortunately, the power play Courtney is pulling isn’t all that unusual.

Ask your lady friend to join you for premarital counseling, where a licensed therapist can help her to free herself from Courtney’s control. I am not promising it will work, but it’s the best chance you have for a successful future together.

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Dear Abby is written by Abigail Van Buren, also known as Jeanne Phillips, and was founded by her mother, Pauline Phillips. Contact Dear Abby at www.DearAbby.com or P.O. Box 69440, Los Angeles, CA 90069.