DEAR ABBY: I am reaching out as a single mother grappling with a serious heart-lung condition. My son’s father abandoned us when I was pregnant, and I haven’t heard from him in more than a decade. Thankfully, my parents have been supportive co-parents during the years when my health made things incredibly challenging. I have always encouraged my son to express his feelings and have assured him that his emotions are valid. We share a strong bond, and he feels comfortable discussing anything with