It's one thing if no one ever said anything, but it is entirely different when she'd been asked before to be more considerate, and even during that very car ride you said you'd asked her to slow down.

If anything is to ever come of your friendship for the future, I don't know. If it were me, I'd want to make sure she understood completely how much she hurt me with her complete disregard and irresponsibility.

I'd point out the many times she'd been asked by myself and other friends to slow down/be more careful, and how she'd laughed it off. I'd point out that she was arrogant and inconsiderate. It doesn't matter if you believe/know you're in control. If you're making someone else uncomfortable YOU STOP doing that thing. You change. She didn't have the respect to get over herself/ego and just drive like an intelligent person, at least for the sake of her friend's multiple requests.

I'm not one to hold a grudge, and it's because I tend to just get it all out.

Depending on how you deal with things, my approach might not really be best.

I think she needs to really understand, REALLY really understand what she did and be incredibly sorry for it, like I want to watch it majorly affect her life and watch her change into someone completely different, before I'd consider bringing her back into my life.

Because, surely, her intent that day was NOT to hurt you, your baby, those other people, herself, anyone.

But she went way, way out of line and it literally changed the path of yours and your fiancés life together forever. She completely disregarded all the signs (hint: when tons of people tell you something about you, it's usually accurate), and acted as though she knew better.

She deserves to suffer for what she did not because it will make you feel better, no. But because in those moments she will find a path to a better version of herself. Someone who hopefully will live a life in consideration of others instead of plowing through it at top speed, acting like she owns the place.