It is natural for you to want to protect a person you love, especially when that person is already suffering from illness. But the impulse to provide protection from further harm can sometimes be taken too far. When "protection" means withholding the truth about the course of an illness, it is important to consider whether the cost of that protection is too high.
You might think the fact that they are dying will be too much for your loved one to handle, but that is an assumption you may want to stop and question. In fact most people who are dying know it, even if they are not discussing it with their families. And in your concern to protect the dying person, you may have missed a bigger issue: the damage that can be done when you place the topic of dying off limits. If you won’t speak about dying with your loved one, he or she is left alone with the subject and isolated with the fear and other emotions it brings.
This state of isolation is harmful to the individual and to your relationship as well. Honesty in a relationship is extremely important, and never more so than in times of crisis. Being honest about the facts and about your emotions may be essential to your ability to stay connected and reach closure with the person you love.