What is the scientific reason for this

What is the possible biological reason I feel this way? I have always had extreme self image issues but they have been getting worse. It’s been so bad my obsession over my looks is genuinley eating me alive recently and I don’t know why. It’s so hard to decanter it from my life when it feels like being pretty would be my only worth. It’s making me so depressed I haven’t gone out other than to work nor have I willingly talked to anyone lately. All I want to do is maladaptive daydream I feel so ashamed of every single thing I do. I feel like a human being embarrassment and I don’t know how to make this go away it’s never been this bad before. I’ve been extremely suicidal to the point I have relapsed and harmed myself and my life just feels like everything I regret doing or not doing. I feel so alone and isolated like there is a wall between me and everyone else. I feel like an alien living in human skin trying so desperately to be a part of humanity. For so long I’ve wanted to be attractive so I feel like some part of me belongs in this world. But I feel like I’m back at square one I feel sick when I look at myself I cry about it every single day. My suicidal feelings have become so much for vivid. I feel trapped in my skin and in my life and I don’t know how to get rid of this. Any advice would be appreciated or even just reasoning.