DEAR ABBY: I have been with my live-in boyfriend, "Kyle," for four years. He has many great qualities, the most important of them being he fully accepts my daughter as his own. He doesn't see her as his "girlfriend's kid" or even a "stepchild." She has no contact with her biological father or any of his family and has blossomed as a person since Kyle has been in the picture.

The problem is, he likes to message women online through various dating and hook-up sites and share sexually explicit pictures and messages. He has never met any of them in person. I have confirmed this. He states he just likes the thrill and attention.

I have expressed multiple times that I consider this a betrayal. I honestly thought he had turned over a new leaf, but I have just discovered his behavior is continuing. I'm heartbroken, but I worry about what splitting up would do to my daughter.

When I left her biological father, she had some major behavioral and emotional issues. I can't bear the thought of putting her through that again. She would not only lose her father figure but also his extended family that has fully embraced her. Do I tough it out until she's 18, or do I leave now? -- HEARTBROKEN IN OKLAHOMA

DEAR HEARTBROKEN: I wish you had mentioned how old your daughter is. If she's in her mid-to-late-teens, she is old enough to understand that you cannot let the romance continue as it is. If she's not yet in her teens, line up a licensed therapist to help you cope with the fallout that happened after your divorce.

Your partner may be a sex addict, which would account for his behavior and his inability to stop. What he has been doing IS a betrayal, and when to draw the line depends upon your tolerance for pain.

P.S. Are you staying with him only to avoid upheaval for your daughter? You must do what's best for her and YOU. There are resources that address sex addiction. Would he agree to try?

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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.

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