Background: My mom is in fact morbidly obese (BMI +40), she's in her mid sixties and had pneumonia a few weeks ago, which she found very hard to recover from. She has also been dealing with difficulties with her breathing for years and I have been having the suspicion that she has sleep apnea. She has multiple health issues because of her weight and she is pretty much one bad knee or back injury away from being bed bound.

Me and my parents had a nasty fight about some other topic. My dad leaves the room and I continue arguing with her. She tries to guilt me into stopping the argument telling me that she almost died because of her pneumonia (she wasn't hospitalised or anything), I tell her that she hasn't been taking care of her health. I tell her that her weight is out of control and that she is morbidly obese and that her health will continue to decline, she screams at me that I am insulting her. My father comes in again and starts screaming at me to leave her alone and threatens to beat me up and then throws things at me (a regular occurrence since my childhood).

I just went to my room and haven't spoken to her since yesterday.

I'm just pissed at her for letting her health decline like this. I will one day be forced to become her nurse in her old age and her weight is going to make that a lot harder. I don't know how to deal with that. And she just doesn't want to hear it. She thinks she will live to be very old and be in good shape, when I doubt that she will turn 70 without being bed bound. I am afraid for her. I want her to live a healthier life. I don't want her to die early or be in bad health. 

I know what it feels like because a few years ago I was even heavier than her. I have since lost the weight and have kept it off by counting calories. I know a lot about the subject and I know what she needs to do to at least lose some of the weight. I have tried offering her help, but she always just listens and agrees and then the next day she is having cakes multiple times a day with my father again.

I'm sorry if this all sounds cold, I'm just tired of the whole situation. I love my mom very much, but I'm scared for her and I have been losing my patience.