In the interim period, he developed a crippling breathing disease from all the cigarettes smoked as a result of the relapse. With proper treatment the original pneumonia would be cured and his breathing capabilities would return to normal. But the smoking now caused a disease that had permanently impaired him. Even if he did quit smoking now, he would have the limitations in breathing for the rest of life. In retrospect, this was a high price to pay to deal with a few days or weeks of fear and boredom.
Smoking is never the answer to any problem.
In most cases, taking a cigarette results in a more serious situation than the problem leading you to take it. Don't make the same mistake this man did. When you find yourself faced with a real problem, work hard to find a real solution. If it is truly a problem that would be resolved when smoking, then with a little time and patience you will also overcome it as an ex-smoker. By not smoking you will have not only overcome one problem, but you will have prevented another more serious situation.