This pertains mostly to new romantic relationships. It could also be relevant to new friendships.

When you initially start dating someone, when is the right time to tell them that you have an emotional dysregulation disorder, and that it will always, to some extent, be the dark passenger, a lingering shadow, in your relationship? And how much detail should you share?

Should we be less candid, and leave it at "I have unstable emotions, I am in recovery and I do everything I can to moderate myself, but there will be times where I slip up"? In the process accepting that we can't share every last detail of ourselves with our partners, AT FIRST, or possibly ever? Is this dishonesty?

Or should we be entirely honest at first? Share all the details of exactly what BPD is and does? Which could make the person hesitant, and maybe make them start looking for cracks, which could compromise the relationship from the very outset?

It's such a fine line. I crossed that line with my very recent ex girlfriend. I told her everything. All the nitty gritty of BPD and my past. The problem was then two-fold:
1) She was ever vigilant for signs of BPD's ugly face. And when you seek, you shall find.
2) This is difficult to admit, but in being entirely upfront, there was a feeling that, "it's okay to let yourself slip into negative, damaging behaviour because you warned her, she knew what she was in for".

Ultimately, I crossed boundaries that I promised I wouldn't because I thought that by being entirely candid with her she knew what she was in for, and would be forgiving, but she left me. The anguish of which is still with me.