Stop Walking on Eggshells: Taking Your Life Back When Someone You Care About Has Borderline Personality Disorder
I've heard good things about the book Stop Walking On Eggshells though I can't vouch for it personally.
I've been thinking of doing something myself. One of the biggest issues seems not to be that people have this, but that others have almost no idea what's going on. Would be great to see more resources
Some of what you wrote stood out to me (berating you and the kids, especially; really not cool) and the fact that you kept repeating the feeling of walking on egg shells...
Let me suggest this read for you: Stop Walking on Eggshells
This is a good resource to get an idea how to cope. Obviously, it isn't going to be a cure, but educating yourself goes a long way.
I married the love of my life. I also married BPD. Had I known it at the time, I wouldn't do one damn thing different. To say it's a pain in the ass to deal with day in and day out it the understatement of the century. I'm comfortable saying that even though we haven't been through much of this century yet.
You need a therapist who actually knows what BDP is. You might be surprised how many are completely ignorant about the disease. They can help you understand how to communicate effectively with someone who really doesn't know who they are.
Is your friend in any sort of treatment? If someone with BPD is seeking treatment, I feel like there is a chance at a relationship. If they're in denial of their diagnosis or if they refuse treatment (DBT or the like), run for your life.
I wish you all the best. I've made it 14 years with a SO who finally decided she wanted to get better a couple years ago. We're not better, yet. We've made a lot of progress, though.
Drugs and the like may take care of comorbidities (bipolar, depression, etc.), but they're unlikely to have much effect on BPD itself.