Keep her safe and calm and try to get her some medical help. If it’s gone on all day, the episode may be more serious/have something medical going on. Good luck, you’re a good friend!

Grounding techniques definitely help. For me it's physical items, like a fidget or even helping to put together a puzzle is a good distraction. Other times soft blanket or stuffy can bring a sense of "safe". Or nice smells like their favorite perfume or calonge or other smells like lavender.

I deal with the exact same thing. Everyone needs something different, but what helps me the most is having someone touch me. Not softly but tight. Like a tight and long hug. Some sort of compression, weight on top of me to help ground me. And my favorite warm drink or food.