Wtf am I gonna do?

So the Face brought it to my attention that mom has been saying for 3 days that she was in walgreens and she was worried mom started smoking again. I haven't been able to be by her a lot lately. I've been sick and for the most part trying to keep to myself. Anyway the Face said that one day she came over and she said that mom smelled like one of her air freshener she used to use to disguise it from people before. I noticed, now that I'm looking for it, that she has also been sleeping on the couch...my point in all of this explanation...I decided when I got home from getting prescriptions for this horrible sore throat that I have had for a week, and after hanging out at Gram's house with the girls and Fred...anyway I decided that I was going to look in her purse to see if she was hiding it again. I found a pack of cigarettes. I told her when she felt that she wanted to start again or was having cravings that she should talk to me. I know it's different for me because I am not having a hard time with it, but I could try to help. I love her and I don't want her to die and I am worried I am going to lose my mom because she is being stubborn. It hasn't even been a month and she is back at it. What do I do? I'm so scared. Dad even commented that he thought she was probably back at it. My throat feels like I'm swallowing knives, so I am going to watch some tv and maybe pass out. I am so disappointed.