Hello GM & welcome to the group~!
I'll echo the same thing as Harley Quinn says ... .sorry that you're hear but happy that you found us. You seem to be MUCH further ahead on your BPD journey then most who show up in the group ...
what I mean by that is that you've already picked up one book for reading and I might suggest another one, "The Human Magnet Syndrome". You've already recognized that you're a serial rescuer and this book might help with that. You can pick it up at your local library, your psychiatrist might have it on their shelf for you to borrow or it's pretty inexpensive on the internet.
My last exBPDgf was very high functioning & a narcissist but was diagnosed with BPD as well. She had a Ivy league eduction for a Bachelors & has more than 1 Master Degree's. She works for a fortune 200 company & makes 6 figures a year. From my education, reading, & therapy BPD has nothing to do with the overall IQ of a person but directly impacts the behavior of that person ... .they are two separate issues. She was incredibly smart but has 8-9 symptoms of BPD via the DSM-5. She knew that she had a Cluster B Mental Illness & attended mental health counseling OFF & ON for almost 28 years now with little to show for it other than the fact I believe she uses what she's learned to manipulate people even more ... .but that's for another discussion.
I digress ... .as you put it YOU want PEACE and you're well on your way to it. Concentrate on "rescuing YOURSELF"

Recognize that YOUR happiness does NOT & will NEVER depend on someone elses happiness. YOU need to learn to like yourself, love yourself, enjoy the time by yourself and enjoy the smaller things in life~!
Here are some exercises for you ... .Get up 30 minutes before the sunrises ... .fix some coffee, tea, a Monster, Redbull or whatever you beverage of choice is in the morning ... .go to the patio, a park, a roof top to watch the sun come up. Enjoy the sounds of nature before & during the sun coming up. It only takes a very small amount of time and it really does give one an "adjustment" to life. Go for a run/walk for a mile or two ... .start to eat better. Go to be earlier & get some more sleep. Go out & get a ice cream since it is the summer & a little warm.
And you as already know seek out a good therapist / Ph.d to help you sort out YOU & why YOU are the serial rescuer that you are. Why are you the perfectionist & codependent that you are and once you do that everything else starts to fall into place. It really does ... .
Feel free to share what you want when you want ... .we're hear to listen to you. We won't judge you because we've been where you've been. Come back as often as you need to but more important as often as you WANT too ... .someone will always be here to help you when you need it.
wishing you the peace & strength you need in the coming days, weeks & months ... .and the knowledge & power to learn & accept things as they are and the courage to move forward on your journey of self discovery !
J