Negativity and Put downs by friends and family

Hello This is my first post. I just need to vent a bit and get some advice. I have had negativity from my friend/ co-worker and my mother. I try to work out 4-5 days a week. I count calories, watch my portions, cut out all processed food as much as I can. I also run/jog and run stairs every night. I eat pretty good most days but I do allow myself cheat days every once in a while. I have lost 20lbs so far.
My friends started her weight loss journey with me. But she gave up 2 weeks in. A few weeks ago she saw that I had a burrito then later that day I had a slice of pizza sitting on my desk. I actually didn’t eat the pizza I gave it to someone else. Any way she brought it up like she was the diet police and was accusing me of eating bad food and that I wasn’t going to lose any weight eating crap like that. This comes from a chick who eats an entire box of rice crispies as her afternoon and bed time snack. She eats 3-4 giant slices of pizza a day from the pizza place down stairs on top of that she drinks 4-5 44OZ cups of coke a day. But she is going to tell ME im going to get fat from a burrito and slice of pizza (that I didn’t eat)
Even if I do cheat I burn so many calories that cheating isn’t going to ruin my weight loss. At one point she accused me of using diet pill to lose the weight. When we first started trying to lose weight we would meet up on walks and she would always find excuses to stop. Tie her shoes, check her phone, and chase some random cat she saw. And after our walk she would go to a fast food joints and get ice cream and say she deserved a treat for working out!! She never even broke a sweat! So I just stopped going with her. After that she quit talking to me as much. Then after her blowup we haven’t talked since. Why do people do this, become diet police? Especially people who make no effort to be healthier?
My mom who is a narcissist also makes negative snarky nasty comments , especially if I have any success. She doesn’t support anything if it doesn’t have anything to do with her. When I told her I lost weight and showed her my before and after picture she just said it was gas. Gas!! Ok so I lost 20lbs because I had gas. Any time I say I lost more weight she invalidates it by saying I should just use diet pills if I want real result. She makes snarky comments when she see’s me eating bread. Losing weight doesn’t mean I cant eat bread! She has been offering to buy me dinner… At taco bell, burger king, McDonalds , or brings home pizza saying she was just being nice. My mom is super selfish and never has offered to buy me dinner before. She saw me drinking a can of sprite. And of course a snotty comment followed "oh its whole sprite not diet". Yes occasionally i will drink soda only sprite and one can. This woman drinks diet soda by the gallons. She drink 2 2liter diet soda bottles A DAY!!! Ok so her drinking gallons of diet soda is healthier then me drinking one can of sprite?!?! And if she isn’t doing that she is picking at the stuff I do eat and tries to tell me what I need to be buying. She has big temper tantrums when I go on my runs at night. She acts as if I am disturbing the household by coming in late (10pm) . I am 27yrs old not 16 and this isn’t her house. I live in AZ and its still 107 degrees out. So night time is my only option. I tried going early in the morning before she gets up that ALSO inconveniences her more tantrums. I feel like she is trying to sabotage me by throwing these tantrums so I don’t go exercise. She is over weight as well and always complains she needs to lose weight. So I think she is mad and jealous that I am actually losing weight. She is super competitive and has to one up and be the first in everything.
On top of that she is working as a temp at a diet company and they give out the product free to employees. She bragged about losing 7lbs the first week (water weight). And has since gained it back but she is always trying to push this crap on me. Im working my butt off to get in shape and she just dismisses my efforts and pushes this diet crap on me. I was looking into water fasting and she tells me her diet pills are the same as water fasting! Seriously!? When I celebrate a 4lb weight loss she in the most snarky nasty tone ask me how did you do that, then pushes the diet crap on me. Uh do you not see me working out and eating right? Her tone and the faces she makes just set me off. I can’t share anything positive around her she can’t allow me to have any joy even over the littlest thing
My sister is also very over weight my eating healthy inspired her so she went and bought healthy food and my mom noticed. One put down from my mom and she was back on the junk food. She also puts my sister down all the time about how she looks. I have the right to be healthy and take care of my body and I don’t feel I should placate to her dramas and emotional outburst when I go to exercise. How do I deal with this woman?