You obviously do not understand his philosophy whatsoever if you have that opinion. He was sick and suffered immensely, but his philosophy is very joyful at its core. He found a deeper, more authentic joy in spite of his miserable conditions. Nietzsche hated nihilism and was a “yes-sayer” in all of life. His views on altruism and love are complicated and it’s true he had pessimistic ideas about relationships, but there is enormous richness in his philosophy about embracing life in all its pain. See his concepts of eternal return and the overman. Nietzsche is widely misunderstood by those who don’t care to have their preconceptions challenged. Was he entirely right? No, but even he insisted on being disagreed with. But his work is dialectic and complex and if you only read it through the surface layer, you will come away with the opposite idea of what he means, because that’s often how he wrote. Any more thoughtful reading will make it very clear he was none of what you suggest.You admire Nietzsche? He was lonely, unhappy, frustrated, sick, angry.
He was smart but did not live a good life at all. Unhappy people can think deeply, but not clearly.
“I am a forest, and a night of dark trees: but he who is not afraid of my darkness, will find banks full of roses under my cypresses.”