Post rage conversation

[Rivermama]

This is my first post.  I’m looking for ideas on how to have a constructive conversation with my adult daughter 23 who lives at home.  This last week she has been very suicidal, feeling hopeless and depressed.  She will come down and eat and talk a little during the day, but in the evenings she begins to dysregulate (sp?). Twice this week she has grabbed the car and left in her rage, driving up the mountain and texting me, her dad, her bf, her brothers that she is suicidal.  So far she has returned in the night and then is about the house the next day as normal (not actually normal, but what is standard interaction for her in this state).  2 nights ago she demanded that I block her bf on my phone.  I did not comply.  I explained that I will not have a conversation with him, but I will keep the line available as it has been important for him to occasionally contact me to let me know something is up and I should check on her.  I am her care taker (she has no job and no other place to live). My refusal to “block” contact with this 3rd person became her focus and soon began the torrent of threats of suicide because of this.  I felt manipulated and stopped responding to her texts.  Her dad (my husband) did remain in the conversation, trying to calm her and help understand what was happening.  Daughters message to father was that the bf is a horrible person, she hates him, it’s over, etc and she just needs ME to block him, then she’ll come home call the doctor and get help. 
The next day (yesterday) she wakes and comes down and when I ask if we can talk, she says no, she needs to leave.  I go outside to grab something from the car and see she is leaving with none other than… the bf.  Of course her father is angry and confused… how was she so cool about leaving with this person today who just hours before was the object of her rage.??!! 
So, that’s the background (way longer than I wish). 
I am no longer wanting to just ignore these rages.  I don’t want her to feel shame for them, but I feel the need to circle back and have a conversation.  For a decade now, the rest of us have learned to just shrug it off as “ well, that happened” and move on.  But I wonder if we are missing an important chance to help recover.  I’m struggling to find words that can be appropriate.  My brain wants to say wtf…but I know that wouldn’t help either.  Does anyone have any ideas on a brief conversation to have with the person to let them know you still live them AND this was not okay?  Thanks. 

Our objective is to better understand the struggles our child faces and to learn the skills to improve our relationship and provide a supportive environment and also improve on our own emotional responses, attitudes and effectiveness as a family leaders