It can be hard to know how to parent when you have BPD pathology in the family. At least that's what I found. My parents were so invalidating so I had to learn how to parent from therapy and books.
I don't know of any books specifically about teen emotions. However, a few books that might be useful:
Parenting with Love & Logic (there is one for teens, too):
https://www.amazon.com/Parenting-Love-Logic-Updated-Expanded/dp/1576839540It helped me find a middle way between permission and authoritarian parenting, what some refer to as authoritative parenting.
I also found I Don't Have to Make Things All Better by the Lundstroms super helpful, especially the part about asking validating questions. The combination of validation wrapped up in a question puts a lot of the responsibility for solving their own problems back on them.
If you are concerned about your child being predisposed to emotional sensitivity, the books on Highly Sensitive Children can be useful, although it does seem like the ones I read all boiled down to: validate their feelings.
There is also Power of Validation for parents, although I found the book spent more time on younger kids than teens. Again, same principle -- to validate their feelings (while sticking to the boundary or whatnot). Depending on how volatile or risky her behavior becomes as she hits puberty, and depending on your concern about whether she is at risk for developing BPD traits, the book BPD in Adolescence by Blaise Aguirre is helpful. I felt very triggered by my son's mood states, including suicidality, and it was really helpful to find a chapter written by someone as expert as Aguirre, comparing regular adolescent behaviors with BPD behaviors.
A book I'm reading now is called iGen: Why today's super-connected kids are growing up less rebellious, more tolerant, less happy, and completely unprepared for adulthood by Jean M. Twenge.
If you have an anxious child (which is apparently reaching almost epidemic proportions), it can be hard to figure out how to help them cope because the whole world feels like a giant avoidance strategy. Hopefully your D9 won't develop anxiety. I saw S16 disappear into anxiety and swallow him whole. I look at pictures of him when he was in elementary school and it's like that child is completely missing
It's wonderful that you are paying attention to your daughter's changes, and being proactive
Even though things are still hard with S16, I know it would be much worse if I didn't try to learn skills I failed to get in my FOO.
