“Why do I feel so hateful that I'm overweight?”

Because you know that you are not who and what you want to be. That builds resentment inwardly and externally. To find help to lose your weight and become happier I recommend you visit: https://obesitymedicine.org/find-obesity-treatment/ to find a bariatric physician near you to start your journey to get you where you want to be and a much happier person. I battle with weight and know exactly how you feel because that used to be me.