Hello TippyBark

Welcome to the son/daughter board.
I’m sorry to hear about your current situation with your 27 year old diagnosed daughter. Was there something specific that triggered her recent outburst of anger? You say that you are lost as how to respond, the first thing is to make sure that you are safe, sometimes it’s best to just walk away and allow her time to process and calm down rather than try to engage with her as that could potentially lead to escalation. Once she is calm it will be easier to talk to her.
You say that she has given up her therapy, has she given you a reason why she did that?
There are lots of TOOLS and LESSONS to be found on the right

You should find them most useful. Maybe take a look at Don’t React, Respond with S.E.T.
Hope to hear more from you x