Active listening is by far the best skill you can learn to help someone through a stressful or highly emotional period.. A "rationalist" might be more receptive to solutions than others, but will probably still appreciate the emotional catharsis of a good listener.
One important thing to remember when being a listener: it's very easy to make the mistake that you're supposed to solve the other person's problems. It might be that the other person isn't actually looking for advice, but rather just sympathy and a reassurance that there's someone who will listen to them. Try to figure out which one they are after, and remember that they may shift from one mode to another and not be fully aware of which one they want, themselves. (I wouldn't recommend explicitly asking them unless they are very, very Tell, for the above re...
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