I went and watched the clip in JBO that set up the events leading up to all that.
She made a little comment and he started roasting her azz to death about her being a hoe, her apparently being molested, and her mom being a hoe and not protecting her.
That shyt got under her skin and hurt her feelings, she was sitting there hurt and holding it in for a few minutes before the crash out.
Broad is obviously very mentally fragile and got a lot of trauma and unresolved issues she probably needs counseling and possibly some clinical help for.