My best friend is suddenly moving away to a different state in a few weeks

I am heart broken. I feel like I'm going to throw up and I can't stop sobbing. I met my friend three years ago, but we only knew each other as friends of friends until seven months ago. Then we spent two weeks together for theater and became best friends more quickly than I had ever befriended someone before. She became my everything so fast, I love her in a different way than I have ever loved. Then, our mutual friend attempted suicide and through her recovery, I was dealing with trauma (from helping find the mutual friend after the attempt) and my friend and I were struggling with grief. We relied on each other through that hard time and she was the only thing that got me through. We've been so close ever since and we were looking forward to our first full school year as best friends.

Tonight she told me that her dad got a job offer a few states over in LA and that they're moving the first week of October. I did my best to keep it together in front of her, but I just feel broken. I'm so, so devastated. I don't know to do and all I can think is that I don't know why we didn't get close when we met three years ago. I got seven months with her and now she has to leave. I can't imagine how she feels, she's lived here for ages, she's a sophomore in high school, she has an entire life here that she has been building and now she has to leave.

It just hurts and hurts.