literally 90% of my friends are acting as if im some object they can just limitlessly make fun of

i know its partly my fault because i always joke about myself and stupid decisions i make (its not like they are mainly a consequence of my anxiety and poor mental health OR ANYTHING LIKE THAT) but they literally cross the line every time im in a group of my friends im in the centre of attention but all they do is make mean jokes about me and im supposed to just not be affected by it