DEAR ABBY: My 18-year-old granddaughter ran away twice last year. She's now living with her boyfriend and refuses to have any contact with her dad. I know my son is very strict, and I'm pretty sure she could just no longer live by his rules. Her mom passed away eight months ago, and my son is all she has besides her sister.

She opened a Facebook page. I was able to write to her a couple of times and she responded. She isn't answering my messages now. I suspect her boyfriend is controlling and is preventing her from contacting her family. I'm also afraid she may be involved with drugs now. She and the boyfriend were recently arrested for shoplifting, and this just isn't typical of my granddaughter.

I have trouble sleeping at night worrying about her. I know she's an adult, but I don't want her to give up on her family who loves her. Do you have any suggestions? Should I go to the house and try and see her, or must we just sit back and wait for her to grow up? Any advice will be appreciated. -- WORRIED NANA

DEAR WORRIED NANA: Do not just sit back. By all means, visit your granddaughter! She needs to know you love her and will be supportive if things don't work out with her boyfriend.

Because she's 18 and now considered an adult, you can't force her to reunite with her father, whose heavy-handed parenting may or may not be the reason she left home. But you can, however, point out that if she needs something, there are better ways to go about acquiring it than shoplifting. You should also encourage her to find a job. If she does, it will increase her independence, not only from her father, but also her boyfriend, if it becomes necessary.

DEAR ABBY: I was recently diagnosed with a stage four cancer. My surgeon has offered me an opportunity to be part of a clinical trial, which my family is aware of. They do not, however, know the details of how far the cancer has spread.

The prognosis for patients in this trial is about two more years. My wife thinks I should share this information with my extended family and friends immediately (although there are few signs that I'm ill). I prefer to remain silent until the disease catches up with me and my time gets closer. Your advice or reader response would be greatly appreciated regarding this very emotional decision. -- KEEPING IT TO MYSELF

DEAR KEEPING IT TO YOURSELF: I'm sorry about your diagnosis. I'm sure when your letter is published there will be a tsunami of reactions -- both pro and con -- from readers.

Of course your wishes should be respected, but since you asked, I am inclined to agree with your wife. Your illness affects not only you but also the rest of your family and friends. If you reveal your prognosis now, it will give the people who love you an opportunity to step up to the plate and offer emotional support, not only to you, but also to her and your family.

DEAR ABBY: My husband, to whom I've been married since July of 2016, has recently caved in to pressure from friends to participate in "swinger" behavior. He wants me to be included, but I really don't want to.

The other female has lesbian tendencies that make me uncomfortable. Her boyfriend is juggling two partners at once, alternating nights for each one. My husband has told him he can do whatever he wants in front of us, which I find awkward and embarrassing.

I don't want to be a spoilsport, but I feel he is being unfair to me. How do I put the genie back in the bottle without ruining my marriage and friendships? We've lived together since 2005, and the pressure is getting worse now that we're married. -- NOT TO SWING IN THE USA

DEAR NOT TO SWING: If your vision of marriage is a union between two people only, then the man you married is not someone with whom you should spend a lifetime. Do not allow yourself to be coerced into anything you are not comfortable with, and that includes threesomes. Much as you might wish it, you are not going to change your husband, which is why it may be time for you to revisit this subject with him and the help of a licensed marriage and family therapist.

DEAR ABBY: I dated a longtime friend, "Austin," for about four months. He had a history of drug use, but had been sober for about four years before he stopped attending meetings.

I have two children from my previous marriage. He knew when we started dating that if he relapsed, the relationship was over. He did, so I ended it then and there. Austin begged me for a second chance and for my help.

I have known his family for as long as I've known him, which is 20 years. He swore up and down to me that he wouldn't relapse again, but he did and died from an overdose. Austin's family blames me for his death because I didn't answer his calls or messages. How can I explain to them there was nothing I could do? -- FAULT ISN'T MINE

DEAR FAULT: You were under no ethical or moral obligation to answer Austin's texts or messages after his relapses. Save yourself the frustration of trying to point out the truth to his family. Austin's relatives are in pain right now, and in denial as well. They are blaming you rather than their son because the truth -- that Austin was responsible for his own actions and his own death -- may be too hard for them to face.

DEAR ABBY: I am a retired lady who often eats alone in restaurants. When I arrive, the host or hostess usually greets me and asks, "How many?" When I reply, "One," the invariable response is, "Just one?" I find the question demeaning and rude.

I have responded with things like "Isn't one enough?" or, "If you prefer groups, I can go elsewhere." I have even mentioned to managers that it would be more appropriate if they trained their hosts not to say "just." Can you offer a better response I can give? -- PARTY OF ONE

DEAR PARTY OF ONE: I think you are handling the situation as well as it can be handled. Sometimes people don't stop to consider the implications of what they are saying. It's impolite for a host to ask, "Just one?" because in some cases the reply could be depressing and cloud the dining experience.

DEAR ABBY: I have grown children. All of them are underachievers. When contemporaries talk about their children getting jobs, getting married, having kids, going on vacation, buying a house/car, adopting a pet, I have nothing to contribute.

My children do not have lives; they work low-paying jobs and scrape by. Worse, they have no ambition to do better. They no longer live with me, but often gather at each other's places to play video games when they are not working. They are not enjoyable to be around.

My life is otherwise good, and I don't want them bringing me down. My marriage is solid, I work hard, we travel a few times a year and enjoy dining out and meeting with friends. We go to sporting events, live plays, concerts, movies, etc. What is a mother to do? -- LET DOWN IN MISSOURI

DEAR LET DOWN: Your children are adults. If they were motivated, they would be doing more with their lives than playing video games and scraping by. Be glad they are independent and have good relationships with each other -- it's a plus -- and continue living your life. You can't live theirs for them. And please stop comparing them to the offspring of your friends and acquaintances. If you do, you will be happier.

DEAR ABBY: I have dear friends and neighbors I really enjoy who have asked me to water their plants and feed the cat when they're away, which is not very often. I enjoy doing these things, and so I always feel awkward when they bring home gifts of jewelry or give me money. I would prefer that they let me do these things for love and friendship, but I don't know how to make them stop giving me things.

Is there something polite I can say to let them know that they should just let me be their friend? I would prefer that to feeling as though I'm being paid for my services. -- FOR LOVE AND FRIENDSHIP

DEAR FOR LOVE: Has it occurred to you that your neighbors bring things back for you because they enjoy giving as much as you enjoy doing things for them? If it hasn't, please consider it.

And afterward, if you still feel that their gifts are too much of a quid pro quo, explain that you like them very much and value their friendship, and they don't need to give you anything in return for the affection you feel for them. I don't think couching the message in those terms would be rude at all.

DEAR ABBY: Why do people stay in bad marriages? It causes emotional harm to the children (if they have kids), hearing their parents argue and name-call all the time. Wouldn't it be better to separate? -- UNHEALTHY RELATIONSHIPS

DEAR UNHEALTHY: Some couples remain in bad marriages because they can't afford to live apart or fear being alone if they divorce. Others have dysfunctional love-hate relationships that, I agree, are unhealthy for everyone, including the children who grow up thinking it is normal. In my opinion, if couples can't live in peace and harmony, they should separate. However, not everyone agrees.