a stranger's tears

An odd little episode at lunch:
I was heading through the cold and grey Adelaide streets, on my way to buy some mushroom & potato soup. I came across a young woman, standing on the edge of the pavement, bawling her eyes out. She looked so unhappy and stricken. I walked up to her and said: "I know it's none of my business, but are you okay?" She shook her head and said: "No." "Is there anything I can do?" She looked at me then, to my surprise, put her arms around me and sobbed into my chest. Hesitantly, I put my arms around her and held her; and there we were: two complete strangers, hugging. I wasn't sure what to do. I just held her. Then, she let go, looked at me and said: "Thank you." Then walked away.
I don't know who she was. I don't know why she was crying. Like I say: odd.
I bought my soup and walked back to the office, my shirt damp from a stranger's tears.