Not to be harsh, but I think it’s worth recognizing here that not all of the problems are necessarily with the OP’s daughter.
One way or another, the OP, despite believing she had a close relationship with her daughter, despite communicating with her every day (not that unusual, but hardly the norm, either), completely (or almost completely) missed at least three massively important things in her child’s life: the boyfriend, the headaches, the utter academic meltdown. Sure, her daughter was hiding things from her, but that kind of behavior in extreme circumstances is rarely completely unilateral. And although I sense that the OP gave her daughter lots and lots of support in preparing for college, somehow the daughter failed to understand how to deal with problems and how to ask for help. None of us is perfect, but that’s at least in part a failure in education, not just an irresponsible kid.
I’m not saying the OP should beat herself up about this. She probably is, inside, although her posts give absolutely no hint that she feels she messed up in any significant respect. It’s done, it’s in the past, time to move forward. But moving forward effectively may not just be a matter of the daughter adjusting her attitude. If I were the OP, I, too, would be working hard to figure out how I contributed to this crisis, and what I could do better going forward to become part of the solution. And it’s not just being tough with discipline and pursestrings (but I’m sure it doesn’t exclude that, either).
My sense from the OP’s posts is that it’s not just a first boyfriend, or lack of common sense, or too many parties. There are some serious issues here, probably not new ones, that both mother and daughter have been in denial about. The first priority ought to be figuring out what they are, because until they do, no plan for moving forward is going to have a big chance of success.