I am so sorry this happened to you. Words do matter and no family member or anyone else should say that. Maybe talk to your mom in private on how much that hurts you. You are young, so try and develop good eating habits. Eat lean protein, veg and fruits and easy on sweets and drink water and milk for beverage and cut out the sodas. Try and get as much exercise as you can by lots of movement and fun active sports that you like. My best to you and your family.

Im sorry that your mother treats you and your brother this way. You don't deserve it. I have an uncle who has fat shamed me my whole life so I know how much it hurts. Next time say something. Bring it to her attention. Tell her how much it hurts and embarasses you. She shouldn't be able to get away with making you feel like crap.

All fat-shamers are exactly alike - sadistic perverts with a shame/humiliation kink. Usually that comes from having suffered something similar themselves; was your cousin a fat boy? Did the fat-shaming uncle ridicule him, for that or something else? My advice is, just say, It's really sick to get off this way, on your own cousin. You need help.

Arianna - How much did your mother weigh as a child? Was her mother thin? In the 70s, 80s, and 90s, people over 300 pounds were not common and teasing the obese was even encouraged. In my experience, if they're around each other enough, you'll see a thin person's disgust at how fat the other person is even if they're nice. If they're not nice they get off on it, often because they have themselves suffered deep humiliation. Your mother weighing three hundred pounds has been fat-shamed every day of her life. and probably loves doing the same to you because of it. I bet she still encourages you to overeat the rest of the time; serves you huge portions and then laughs at you for eating them all- Thin people can really be cruel.

I'm not sure how much she weighed as a child but as someone who was teased in highschool for being overweight, she should understand how much that hurts and shouldn't to it to others, especially her own children.
If someone hurts me, why would I hurt someone else in the same way? I know how it feels and I would never want to do that to someone else, yet that's what she does.

Being obese is about food choices. The food industry want people to be fat and so does the medical industry. There is big money in exploiting the obesity epidemic.

In the 1970's 3% of Americans were obese while today it's 36% or higher. Why do you think that is? What do you think changed?

Do you think you are powerless to change your eating and consume the correct amount of calories from here on?

Do you know how many calories are required for an 18 year old female to maintain 280 lbs? It take about 4000 a day.

Do you know how many calories you need to be consuming to maintain a health weight? Answer: Under 2000.

Do you know what you Basal Metabolic Rate is? It's about 2800 calories per day.

If you were to eat 28oo calories this week you would lose about 3 pounds. The way it works is if people eat at the BMR they lose 1 pound per week per 100 pounds of body weight.

You BMR is approximately you body weight times 10.

You are probably fat because of what your 300 pound mama fed you. She fed you the food she liked. Like a lot of Americans she picked yummy yummy food over nutrition. Now you are used to that "foodscape" and that is why the two of you are obese.

When you become obese you develop fattitude if you're female because of the stigma. You felt fat shamed but were not fat shamed. The obesity rate in Japan is very low and they point out shameful behavior. The Japanese outlive Americans by about 6 years and Japanese women are exquisite in looks and personality.

Your mother is a victim of her food choices as well. Your situation is very similar to alcoholism. If you tell a drunk she's a drunk she'll feel hurt but you can't sugar coat this stuff. When drunks admit they're drunks they have a better chance of recovery, You and your mama abuse food, There is a word for people who chronically eat too much. Alcoholics drink themselves into early graves. You and mama are eating yourselves into early graves. That's not fat shaming. That's what you need to admit,

One more thing.... Some people may be tone deaf but I don't think most people go out of their way to say mean things to fat people. You don't hear fat men whining about being "fat shamed". I have seen first hand slender women being body shamed by big girls. It's happened to my wife. Attractive women get picked on all the time and there is a huge double standard against fat men by women. Lean men and fat men hang out together. I have seen this for years. Fat acceptance has very few male members.

Your mother may be awkward in her approach but I doubt if she would like to see you suffer the co-morbidities associated with obesity such as diabetes, heart disease, hypertension, joint problems, high risk pregnancy etc.. You may want to ask yourself what's meaner, diabetic amputations, joint replacements, heart surgery, etc...

Here's some tough love. https://www.youtube.com/watch?v=ZM8-rjrL2TQ&t=30s This guy nailed it! I based what I wrote on what this guy said in this video.

That's awful. Have you ever tried to talk to her about it privately? As an overweight person who has raised overweight people I wonder if her comments are somehow born out of guilt? In the long run the why doesn't really matter the hurt does.
Hamg in there and if you can't talk to her about this hopefully you can to someone,

Also I would recomend you do your own nutrition research as there is no end to thories out there. Yes reducing calories is the answer but how is the question? For me sugars/grains are the devil and I eat them in adfdictive fashion. I struggle with it and I'm still trying.