Hate my body. Not feeling sexy

I keep seeing post about how you shouldn’t body shame and everyone has different body and you shouldn’t make fun of people for their body’s and while reading the post I’m like yes exactly. But then I go to the comments and half of them are like “you unhealthy” “I just want you to live your long life” “your fat so your ugly” “your ugly when your fat” “fat is bad and your so unhealthy”

I can literally only eat one piece of bread and gain 40 pounds I can eat nothing and still gain weight. I’m 3rd grade I was no longer skinny after some surgery I had. And I have the slowest metabolism on earth. And I’m already suicidal to begin with so seeing people saying that I’m super unhealthy and that I’m ugly and then turn around for seconds later saying my girlfriend is super hot and they tap dat even tho she’s way more than me and only eats junk food but she’s skinny so she must be so much healthier than me right. Everytime I see some skinny person say how fat she is i feel bad for her because she’s insecure about her self but it makes me feel worse because if they see them selfs as fat then what do I fucking look like to them. And I get bullied all the time at school and I get dirty looks everywhere i go. I just.... everything weight is brought up or I remember it... it makes me want to kms more and more but I made a promise that I would have kids with my gf and I don’t like breaking promises but it’s so hard when everyone tells you to do so just from your fucking weight.