There are people with depression who are able to function apparently well and then shock friends and family with their suicide.
That is very true. Two years ago, the goalkeeper of Germany´s soccer team suddenly committed suicide. The whole country was shocked.

I mean, he was part of the national team, he should have taken part in the World Cup, that is more or less the dream of every soccer-player. If he did not feel good and successful, who should? As it turned out, he had been suffering from depression for years, but not only had he succeeded in keeping the public in the dark, during the last days before his death he had even
managed to fool family and close friends. In his farewell letter (that was found after his death) he apologized for that and said that he knew that he had to deceive them and pretend that he was well because else they would have watched him so closely as to make it impossible for him to carry out his plans. He really knew how to keep up
appearances...

I was also, at the time, very shocked and sorry for him. I am not necessarily fond of somebody just because he happens to be good at soccer. But Robert Enke was always friendly and modest, very committed to the charity he had founded, and what he said was always worth listening to (which is not always the case with soccer-players, with some it is painfully obvious that they are paid for how they play, not for what they say...)
CP Masako could be doing everything that her doctors tell her to do and still be having a hard time appearing in public, which is why I think that accompanying Aiko to school might have been as much therapy for Masako as it was help for Aiko.
It is interesting that you say that because that is what I have been silently hoping, too. When a child is afraid of going to school, under normal circumstances it would certainly not be the solution I´d choose to send her mother with her (or with him, as the case may be). But the situation of the imperial family is, in many respects, not normal, so it is always very difficult to judge without knowing the exact circumstances. After all, Gakushuin and the IHA could not even find an agreement regarding what to tell the public about what really happened to Aiko. Gakushuin said one thing and the IHA another

(which is, I suppose, rather unprecedented).
But, seriously, when I heard that Princess Masako bore her daughter company at school five times a week, I could not help thinking that this was probably a much bigger amount of communication with the outside world than she has had during the last 7 years or so. It is amazing that she was able to do it. Maybe she herself was amazed which might have a positive impact on her self-confidence (hopefully

). I suspect anyway that the crown princess uses to feel especially bad on very formal occasions (plus probably the fact that this usually means that she has to bear the artificial smiles of her in-laws). It seems to me that she is able to cope much better when she feels that she is being of some practical use, like with her daughter or also in the case of the earthquake victims whom she has been visiting alongside her husband – as far as I can see, whenever he was scheduled to do that, she has been by his side.