I think he did the correct thing. it seems that talking to her did not get through, so you have to go to their level of understanding. she made the post's(notice there where more than one) for attention, so the only way to get through to her was by using the same thing, attention. that is why he shot the computer, because it caused attention.
and apparently it worked. I went to his facebook just to look and apparently she is doing great. I don't think anyone thinks that she doesn't have access to computers, it's pretty much a part of a school curriculum anymore, but being in the IT field I'm sure there are plenty of home computers she can use for homework and stuff.
all hail the crimson king