Not sure how to deal with a friend reaching out again.

Hi,

I have a friend, who has been struggling for a very long time 4 years +.....I thought I was being supportive, Hind sight think I was enabling..... 😕 Xmas day she had a break down at a mutual friends, saying she couldn't stay for lunch she ranted, cried, screamed, then, relaxed.... all in the matter of 10 mins then left drove off and went home. Fast forward 4 days, we go visit Ill friend, to see how she was, we took her to chemist to get meds, offered to buy her lunch, she said no, went cranky and said we had hijacked her and she wanted to go home. She got aggressive in the car at me turning the wrong way.... and jumped out the car at the lights, a car hike from her house. Friend and I were shocked and upset.... we let her walk home. And went home ourselves. I sent a message saying, how you going? Are you still angry?.... now she's answer Hi, I'm ok now, I'm not angry anymore. Well, now I don't no how to reply to that. She didn't apologise. No how are you? My delima..... how do I reply and what /how do I set boundaries with a friend.

Granted on the grand scheme of things this isn't a crisis, but I would like to hear your input.
thanks for reading 🙂