What i understand from ur theory is that the loved one brought back with the harrypotter.wikia.com/wiki/Resurrection_Stone has only the same appearance as the actual spirit, and this "fake-ghost" -let's call it- tries to lure the user of the stone to die (if that's what u meant)
Well, idk, i believe it brings the actual spirit since it's not what that fake ghost says that pushes the user to 'go die' but rather the longing: what happened to harrypotter.wikia.com/wiki/Cadmus in harrypotter.wikia.com/wiki/The_Tale_of_the_Three_Brothers ...
<Finally, the second brother, driven mad with hopeless longing, killed himself so as truly to join her.> _the harrypotter.wikia.com/wiki/The_Tales_of_Beedle_the_Bard _
And, for harry's parents, i believe they were actually encouraging him , i mean they can't tell him not to go to Voldemort ! He has to, that WAS fighting back ! It was the only way, it was the right choice. If they said the opposite then I'll be suspicious.
But still, u do have a point when u say the stone lures people to die that was the harrypotter.wikia.com/wiki/Death 's aim in the story, it was only harry who used it as a relief instead of a cause of death as far as we know.
And, i think u might have a point about their behavior what i mean is Cadmus's fiancé was described "sad and cold" in the story, but honestly i don't expect any brought-back ^^spirit^^ to be enthusiastic and start acting normal like...death is tragic isn't it...