If she's calling you up to rant about issues like that, especially 'you never loved me' she's still conflicted. She may also be processing some guilt. No point mind reading though. FWIW, I think if you keep doing what you're doing, you'll be the one deciding whether you want to take her back. I thought your ' I'm not going to argue with you, you've been a great mom' response was perfect.
Sounds to me like she's cracking and as long as you don't play her game and keeping confusing her with your 180's you're doing well.
I don't think there's anything unusual about the 15 month time frame. That's why everyone says it takes time.
