Why am I like this?

Sometimes I refuse to eat. Or lose my appetite. Like if something bad happens or something puts me in a bad mood, I’ll be hungry but I won’t allow myself to eat. Like today I know I wanted pizza but didn’t know from where so I told my boyfriend to pick (he’s picky about his pizza anyway) but he didn’t want to pick and told me he doesn’t want to deal with it today and to just pick. But his tone irritated me so I just heated him up leftovers and didn’t for myself bc I lost my appetite. Then he put the leftovers away and told me he’ll eat once I eat. Now I don’t want to eat at all today. It’s been like this since I was a kid. I’ve gone 48hrs without eating and even tho I’m hungry it’s like I’ve convinced myself I don’t deserve to eat ?? I hate that I’m like this