Why do I neglect myself and constantly compare myself to others? Could childhood trauma and my family dynamics be the cause?

Why I am so self neglect? Never love myself, always compare with others? Is my mom narrsisst? Total we have 4 son . I am 4th, 3rd one is died from hiv in that time my age is 5-6, later my father suicide at my age around 10 years, my 1st and 2nd brother I had never talk with them like friend,I can't open up with them,i never gets basic things like clothes,love , if i won't listen to those brothers I got punishment, now i am currently trap with narrsisst gf, figure out month ago she is narrsisst,she don't want leave me,even i say many times, block her, is my mom narrsisst? Or my whole family narrsisst? Why i am suffering from childhood? What is the cause?even now my confidence completely down after two years of narrsisstic gf relationship, constantly stress, i never make a friend, i think many times before speak a person, I can't talk with a person without any reason like friend ,why?