Not a vet, so just sharing some personal experience...
You're right, this is some major league level of indecisiveness. It's interesting that she turned around after driving 6 hours. Plenty of time to think by herself. It sounds like a W who wants to make her own decisions, not someone who wants to be guided. The issue might be that she doesn't know her goals -- this internship would have brought her closer to... what? If you don't know what you're aiming at, then it's hard to know where to shoot.
Many WAS seem to end up much worst than they expected. You might have seen it in my sitch this week, when my WAW reported being back on medication and insomnia less than 5 months after leaving me. I don't know either what it means. I guess DB says we shouldn't think too much about it. Some of them might see it as just a phase, something they have to go through before they are happy again. Just keep going seems to be the mantra of my WAW.
My WAW doesn't call multiple times a day, but she did try to keep in touch daily about "fun" stuff. On the advice of the vets, I cut it off. I responded lightly then stopped responding. Then I told her I needed space to move on. I can tell she lost something that she wanted. The goals are to help us detach and to let them miss us. I don't know yet if it brought us closer to R, but I can say that it has given me much more calm and focus in my own life. With your frequency of contacts, you're almost like those people with an in-house separation -- it looks like hell. If you can't detach and want to, you can consider cutting it off more. If you so decide, you can go as far as telling her about it and why, like I did (very briefly). Wonka is one of the vets that advocates a strong boundary.
By the way, excellent thing that she noticed the 180. You're new self sounds good. As you know, the goal is that we become these people for good, not just use it as a trap to attract them back.
M39 D6 D3 (at S) S 2014-09 D 2016-09
"You can't start a fire sitting around, crying over a broken heart" - Bruce Springsteen.