Uh-oh, Receiver. However much you want the Bearer of You can't handle the truth to tell you everything – with Tell me the truth perhaps –accurately or otherwise, they doubt your ability to cope with it. However frustrating this may be for a Receiver who feels themselves better able to judge their capacities than the Bearer, You can't handle the truth provides ample implication that whatever revelations may be forthcoming are unlikely to be pleasant ones.
Any Receivers wishing to disabuse the Bearer of notions of their fragility can send I can take it to suggest they are categorically mistaken, or Please to request the Bearer reconsider, while Tell me the truth repeats insistence on honesty and Is this the end? indicates continued refusal may have profoundly negative effects. Surprise me laconically requests the Receiver be allowed to judge their own emotional capacity; What's happened to us? laments the need for such discussions in the first place, and You've gotta be kidding me asserts in no uncertain terms that the Bearer has severely misjudged.