Should a person punish herself for wrongdoing by depriving herself of a value?

A friend of mine destroyed her phone in a fit of anger over a difficult situation that wasn't her fault. Now my friend feels guilty about her outburst. She thinks that she doesn't deserve to properly replace her phone, as that would reward her irrational outburst. She wants to either buy a cheap phone or go without a phone for a while. That seems needlessly self-destructive. How can I explain to her that she really ought to replace her phone?