Depression - Low Self Esteem

Hi, everyone. I'm super new to this so bear with me. For context, I'm a 21-year-old female. This is really hard for me to talk about because I feel so embarrassed about it. So early last spring I began to notice that my hair was becoming super thin. I went to about a dozen doctors looking for answers, but they all told me it would be fine and grow back. Months past and it didn't improve. I became very depressed, so much so that I could barely work and I literally would lay on my floor crying begging God to let me die. I cried every single day for over a month. I know this sounds like an overreaction on my part, I mean its just hair, right?  But for me, it hit me so hard. It's like the hair thing wasn't the sole cause of my depression but was what pushed me over the edge. I recently went to a dermatologist who said it was most likely something genetic and proscribed some medication that would help grow it back. I still get depressed some days and my self-esteem is at an all-time low right now. I hate myself and the way I look. It's like I lost my carefree self and I can't seem to get it back. I'm constantly comparing myself to others and can't seem to stop. Sometimes it gets so bad that I can't enjoy watching TV because I compare myself to the actresses the entire time. I feel ugly and inferior and I don't know what to do. I'm sick of feeling this way, it's emotionally exhausting. Any advice on how to deal with this?