Suppose that Christ commanded that we love our enemies and love our neighbor even as we love ourselves because such love is an essential condition of blessedness or supreme happiness. If this is true, as I believe it is, then God could not possibly bring blessedness to one person without also bringing it to all.
Here is why. If I truly love my daughter even as I love myself, then her interests and my own are so tightly interwoven as to be logically inseparable: any good that befalls her is then a good that befalls me, and any evil that befalls her is likewise an evil that befalls me. I could never be happy, for example, knowing that my daughter is suffering or in a miserable condition--unless, of course, I could somehow believe that all will be well for her in the end. But if I cannot believe this, if I were to believe instead that she had been lost to me forever--even if I were to believe that, by her own will, she had made herself intolerably evil--my own happiness could never be complete. For I would always know what could have been, and I would always experience this as a terrible tragedy and an unacceptable loss, one for which no compensation is even conceivable. Is it any wonder, then, that Paul could say concerning his unbelieving brothers and sisters whom he loved so much: "For I could wish that I myself were accursed and cut off from Christ for the sake of my people" (Romans 9:3)? From the perspective of his love, in other words, Paul's own damnation would be no worse an evil, and no greater threat to his own happiness, than the eternal damnation of his loved ones would be.
God could make us "happy" whilst our loved ones suffered in hell only in two possible ways: either by concealing from us the magnitude of the tragedy (blissful ignorance), or by giving us a callous and stony heart, so that we no longer truly loved those who were lost. Both of these possibilities, however, are incompatible with true blessedness. So in the end, it is logically impossible for God to bring blessedness to one person without also bringing it to all