Starfire is the one tha tdelivered the deathblow to Addie, after Grodd had basically rendered it to a point of a mercy killing.

In Birds, where my canon comes from, by the point we've reached, there have been vague grumblings between the women (Huntress, Babs, and Dinah) over the men in their life. I took the liberty of expanding a bit on that, using fanon subtext (if Dick's with Roy, and Dinah knew about that, and Dick was STILL after Babs...would not set well with Babs bestfriend...).