Its so frustrating when u feel u have to parent ur parents sometimes, my mum has terrible anxiety and stays in bed all day. I can't fix it. I have spent so much energy worrying about her and trying to help her and it's just caused me pain and hurt. I was advised by my counsellor to just stop trying to fix her. Fix myself first. And I think she was right, there's only so much you can do for someone else. Your mum was obviously raised like that and has learnt this weight obsession from her mother, so it's really not her fault. Maybe try and ask her about it rather than getting mad at her. Questions are a great way to get people to realize their own problems. Or download some weight loss ideas and print them off. They will all say what she's doing is unhealthy. Goood luck anyway!