Best friend vent

This is more me venting than a rant. I’m not angry, just sad. My best friend and I have been best friends since 1st grade, so 16 years. We were super super close until I moved away for college. Even when I first moved we texted all the time and said we missed each other. Then, she broke up with her boyfriend and completely changed. She started smoking weed and hanging out with different people. She rushed into a relationship with a guy who had been in jail. He got her to do all kinds of drugs. I transferred to a school back home for my last two years of college, but I still didn’t see her much because of him. They only wanted to hang out with their friends who did Molly. They broke up a while ago, but she still does drugs. He was in jail again for heroin. She recently got into a bad car accident while drunk and got her license taken away. She had a wake up call and stopped everything she was doing. That was about 6 months ago, and now I think she’s doing drugs again. Last week, I almost had a heart attack when one of her other friends messaged me on Instagram asking me if I’d heard from her and she said she was worried about her. I had texted her a while ago because I was sad and she never replied, which is super unlike her even when she’s on drugs. I know she recently started talking to a guy again who brought cocaine around her (something she used to have a problem with). I just want the old her back. No one understands me like she does. We have the exact same sense of humor. I miss her so much. I can’t help but think that if I hadn’t gone away to college, she wouldn’t be like this. She always has had a bad sense of judgment and I’ve always been the one to kind of show her what’s wrong and right. I’m going through a lot right now with losing my job and other stuff and I just wish I had her with me. I know she’s going through a lot too, with paying for her DUI and work but if she’d just let me in, we could be there for each other. It seems like she only wants to hang around her friends who do drugs, because the girl who messaged me on Instagram doesn’t do any drugs either. She told me to keep reaching out to my bestie because she needs people like me in her life, but she doesn’t respond when I do, so it’s hard. I’m just so worried about her. I don’t know what to do anymore. ☹️