Struggling

I know I have some form of anxiety, but I don’t really have a name for it, I just know my mental health is unhealthy. I’m in high school. My self esteem is very low, but only one person knows how truly bad it is because I constantly have to hide it. I’ve struggled with suicidal thoughts and self harm for a year now. I developed a crush on a really close friend of mine, and those feelings honestly kept me from possibly ending my life. Now it’s a year later, and we are extremely close friends, but I found out he doesn’t feel the same through another person. And him and I have never talked about it, so I’m just left to my thoughts to wonder if I ruined everything with him because I have feelings. I’ve started bottling up my feelings again and closing myself off again and my anxiety is unbearable. And I had my first self harm relapse in 3 months and I’m really ashamed of myself. Does anyone have any advice?