Im not living anymore

Im just 19 and from the time I left elementary school life just kept fucking me up I was always a loner and all that but now it’s unbearable I Don’t really have any strong connection to my step family they don’t care about me just my grades and how I’m performing in school also I visited psychiatrist and im pretty sure he didn’t believe me when I told him I want to kill myself and just made fun of me also my now ex didnt really try to help I feel like I’m all alone and it’s probably not feeling idk this is my first ever post on Reddit I don’t do this kind of stuff I just don’t know what to do