What a stupid neologism.
I know language doesn't have to make sense, but to me 'ghosting' seems to mean the exact opposite of what it's supposed to mean.
Think of it, a ghost is a dead person that hangs around and bothers you in this world when it should have gone to some other realm, presumably.
Aren't there enough existing words and expressions that mean the same thing: ignoring, stonewalling, etc...?