DEAR ABBY: My sister, "Margaret," cheated on her husband for 30 years out of their 30-year marriage. Her husband had a visual impairment that led to blindness, and for the last 10 years he was completely dependent on her. I'm the only one in the family she confided in about her affairs all these years. We're both now in our 60s.

Margaret's husband died last year of cancer, and then her boyfriend left her because he wanted a real relationship and she did not. She was devastated about both events, but cannot let go of being rejected by her boyfriend.

I am sick and tired of hearing about this boyfriend and his and her choices. I never approved of how my sister lived her life. Margaret's husband was a good man who would do anything for her.

I recently suggested she speak to her grief counselor about this so she can find some peace in her life. Now she tells me she has cut me completely out of her life, but she continues to send me nasty emails. She's also bad-mouthing me to my brother and my children (who know nothing).

How do I deal with this?

- Tired of Her Dirty Little Secret

DEAR TIRED: You gave your troubled sister some good advice; it's a shame she didn't heed it. Now here's the way I recommend you deal with what she's doing: Tell your brother and your children everything you have written to me. After that, direct any emails you receive from your sister into trash without reading any more of them, ever.

Do that, and you will find that, like magic, there will be less drama, turmoil and stress in your life.

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.