I'm 90% sure that I am clinically depressed. please help me!?

So it started a few years ago, my life was not going well, and I started to slit my wrists and attempted suicide once. My parents found out about my suicidal thoughts, but I pretended that I wasn't serious, so they didn't get me a therapist. Since then I've had major trust issues. I recently lost my best friend because she told me I was too clingy, but she doesn't understand that its because I have problems. I never tell anyone because I don't want them to think I'm a freak, or laugh at me. I act happy on the outside, but I have every symptom of clinical depression. I want to get a therapist and anti depressants, but I don't want to tell anyone. Even though I have suicidal thoughts almost every day. Especially since I lost my best friend. The thing is, that I feel very guilty for even having these thoughts, I have a privelaged life and it makes me feel even worse because I don't deserve what I have. Please help me, I don't know what else to do.