I feel so guilty

I'm not sure if this is the right place to post this. If it is the wrong place I am really sorry!

My best friend and I have been best friends for nearly 12 years ( we are both 20). She's like my other half lol but we aren't dating but there have been a few cases where people thought we were when we really weren't just because of how close we are. We are borderline inseparable. I have an apartment. She still lives at home. She has a key to my place and my parents place too and I have a key to her parents place because we are that close and come and go as we please.

Well she's been acting a little weird for probably 2 months (hormonal I'm sure!) But she's like I'm not pregnant geeez I'm responsible. But she's been really weird and eating things she normally wouldn't eat and cleans everything alllllll of a sudden and reads too much into everything now.

Well the other day she wanted to go to the bar. I was studying for a huge exam which she already knew about so I said I couldn't because I needed to ace this exam. She was begging me all evening to come out with her and I kept saying no. She got fed up and said I'll go with these other people then. I was like ok have fun.

I got a phone call from her parents around 2 am asking if I've spoken to her and I said no she went out to the bar. They were like you didn't go with her? They almost seemed appalled that I let her go out without me. And continued to inform me that they got a call from the hospital saying that she was there and they were calling me to find out what had happened as they were on their way.

So I scrambled and got my ass to the hospital

Turns out she didn't set up a DD (normally I'm the one to do thatt) So she just started to drive home and ended up crashing into a center median. She broke her collar bone, broke a few ribs, had internal bleeding, a concussion.

I felt so guilty. If I had been with her this never would have happened. Because I'm the responsible one who sets up a DD or is the DD myself and I'll tell her if she's had too much to drink and insist that she stops and she listens but when I wasn't there for her look at what happened.

Worst best friend award goes to me.😣💔