You know Irish, that were it not for the life you have made for yourself and your girls, you would have one of the saddest stories on this site (I think the same of dear peacetoday as well--you guys are the real deal).
She is sad. She is a mess. I thought she was a happy go lucky newlywed with a new residence and friends, and look, now kind-hearted people fighting her battles for her, ready to swoop on the baddies that cut her loose those awful three years before.
Sadly the suicide stuff is probably manipulative. My H (you know, the infamous texter) has sent the kids suicide videos. I think he cares about his image a little too much to display his manipulation for the masses. My kids are, I think, around the same age, maybe a little younger. I can tell you that these manipulations have not been successful. I think your girls will probably see through this, and even if they did communicate or meet up with her, they would quickly figure it out.
If it is real, and she does carry it out, that will be her choice. You have been kind in asking the others to help her. They are the ones she turned to. They are the ones with insight into her life.
I'm sorry that she can't leave all of you alone. I'm guessing she is a borderline from her various antics and while I think they can be helped if they seek it out, they do actually have to seek it out.
I hope your relationship is going well and the lawyer letters have ceased. I hope the roses and cards to the girls on their big days are falling away. I hope she does get help one day and her girls can get some answers. But you are still the standard for how someone should lovingly detach and get on with the task of living.