I found this interesting as well, and when my g/f has been stressing I try not to help but just listen and gently offer some ideas. I've found that if I tell her how much I love her when she's stressing, and remind her that I'm on her side it goes much better than trying to 'solve' the problem.

Usually, she will tell me the next time we talk, or the next day, that she's sorry for what she said or how she said it, or for being upset like that in the first place. I just love her with all my heart.