When she began crying, vulnerable in the middle of the room clutching her bath towel, I looked at her intently for a few seconds, walked up, gave her a strong hug and a cheek kiss, wiped one tear with my thumb, and then let go to pour a couple of drinks for the both of us. I didn’t ask what was wrong, I didn’t ask if there was something I could do, I didn’t ask how I could make it better. I didn’t even ask if she wanted a drink. I just put the drink in her hand. Everything was done in silence... She was emotionally cold for about a half hour after that, then as we were lying in bed later falling asleep, she rolled over and nuzzled her head in the nook where my arm meets my chest. She was smiling.

...

Here are the rules for dealing with a spontaneously crying woman:

Don’t worry about why she is crying.

That reaction is warm, nonverbal reassurance. 

If you suspect that the cause of her tears is something you did, you should let her express those reasons on her own time. 

Give her a glass of water or wine while she is crying.

For the love of god, DON’T PLEAD WITH HER TO COMMUNICATE HER FEELINGS.