Dear Prudence: My father is 77 years old. After more than 50 years of enthusiastic smoking, he has finally been diagnosed with Stage IV lung cancer. I'm 37, and since I can remember I have worried that this day would come.

He loves to talk about himself, so he calls me and goes on and on with the latest updates, and how he is sure the next round of treatments will cure him. (The five-year survival rate for people with his diagnosis is 1 percent.) Beginning when I was a small child, I tried to get him to quit by using persuasion, anger, heartfelt letters, throwing out his cigarettes, even family therapy a few years ago, all to no avail. He would often get angry and defensive and even called me "selfish" for describing how his smoking affected me.

I'm fed up and having a hard time mustering sympathy for his self-inflicted disease. And he is still smoking! Part of me feels that I should be a loving and supportive daughter to my ill father. But my feelings are so clouded by anger that he has chosen cigarettes over his health and more years with his family that I don't feel like responding with concern and good wishes. Is there anything to do but swallow my feelings and feign polite concern?

Prudence says: According to figures from the Centers for Disease Control, today the American male's life expectancy at birth is just over 76 years. So while I understand you feel your father's inability to face down his addiction robbed you of more time with him, you should recognize he has lived a full lifespan. Since you are approaching middle age yourself, if you take a mental survey of your friends, I'm sure you'll note there are already some who didn't get as many years with their fathers as you have had with yours. As time goes on, you will see many more of your friends caring for parents whose final years are an agonizing slide into dementia.

I despise smoking, and thank goodness the rates continue to go down, to less than 20 percent of adults today. But your father came of age in an era when almost half of adults smoked, and that infernal habit has racked up a huge death toll.

The statistics make clear that your father will be added to this list soon. But it's up to you to decide how to spend what time you have left with him. Imagine it's five years from now and your father is gone. I doubt you will look back on those last days and be glad you spent them seething with resentment that he couldn't quit smoking.

Angry as you are, try to find a way to open your heart and have some sweet, loving times with your dad, even if they take place outside the hospital while he has a cigarette. There's no point in his trying to quit now. You know he'll extinguish his last one soon enough.

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