DEAR READERS: A great many of you wrote in with stories of your own about the pain of caring for a loved one who is in the middle of an addiction. Below are two letters that I hope bring some comfort to those living with loved ones who are struggling with addiction to know they are not alone. I also encourage family members to attend Al-Anon meetings. DEAR ANNIE: About a week ago, “Heartbroken Grandpa” sent a letter about his granddaughter’s addiction and death. He wonders if there was something else he should have done. I’ve been there. My son also had an addiction, but his was with alcohol. …