DEAR ABBY: I am a single male in my early 50s who looks younger. A married couple approached me and expressed their desire for me to become intimate with them as a couple. They are only acquaintances.

I was surprised but interested when they told me they have an open marriage and would like me to participate with the wife. They are into threesomes, swinging and swapping. I have never participated in such activities, although I admit that I am now very curious.

They know I am a religious person and told me that they don’t consider it to be adultery or coveting since they are willing participants and there are no secrets or desire to break up their marriage. I told them I’d think about it and get back to them.

When I discussed it with my married brother, he was all for it. But when I talked about it with my divorced sister, at first she thought I was trying to recruit her as a participant, which I was not. Once I cleared that up, she voiced no opinion.

I am a clean-cut boy-next-door type of person. I don’t flirt with women, and I’m discreet about my personal life. This could be why this couple approached me. I would appreciate your thoughts. — CURIOUS IN CALIFORNIA

DEAR CURIOUS: I’m glad to oblige. Because you are a religious person, look up the definition of adultery. My dictionary defines it as having sex with someone other than your spouse. Covet means to lust after. This swinging couple appears to have their own definition of those terms, which do not mesh with reality.

That said, being in your sixth decade, you are a big boy, and the decision whether to participate is strictly up to you. I know the offer is flattering, but it might be interesting to know what your religious adviser would have to say about this. Before proceeding, perhaps consider seeking advice from that person.

DEAR ABBY: Six years ago, I retired to care for my wife of 34 years. She was on multiple meds and wheelchair-bound, suffering from high blood pressure, alcohol and nicotine addiction, chronic depression, morbid obesity, advancing kidney failure, severe arthritis and worsening dementia.

Throughout the remainder of her difficult life, I was her only caregiver. Her son and daughter were “too busy” to help, although they live only a few minutes away. (Her “too busy” daughter didn’t even have a job.) During the final year of my wife’s struggle, not once did they visit her.

After she died, they spread the word on social media that she died because I didn’t take care of her. I don’t know if it was to deflect criticism from themselves or to assuage a guilty conscience (if they even have one). What kills me is they told that same lie to my grandchildren, and I can’t call and tell them the truth. My son-in-law threatened the kids that if they spoke to me, he would take away their phones.

It has been a year and a half, and this mess still breaks my heart. Any suggestions? — UNHAPPY GRANDPA

DEAR GRANDPA: Unless there is a chapter missing from your letter, what your children have done is not only inexplicable but also despicable. To alienate you from your grandchildren is heartless.

However, what’s done is done. You know you did everything you possibly could for your late wife. Now go, live your life to the fullest and stop looking back because you richly deserve every GOOD thing life brings your way.

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.

Good advice for everyone — teens to seniors — is in “The Anger in All of Us and How to Deal With It.” To order, send your name and mailing address, plus check or money order for $8 (U.S. funds) to: Dear Abby, Anger Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Shipping and handling are included in the price.)