i still dont know

heyy so I just wanted to ask where am I wrong, I mean he tells me that no one should know that I know him and he roams w his ex in entire school, he goes and have coffee w her, and they keep the same pfp but when I flirt w guys its wrong? aldo we arent in a relationship its just a situationship since a year, when he does all of this i cannot say anything but then why am I guilty, I begged him to treat me right but in the end all I got was blaming, yelling at me, blaming me that I start fights, abusing me mentally, making fun of my insecurities, my only mistake is I love him too much, im sorry but needed to vent it out. hope y'all have a good day cause mine indeed isnt.