Our own Morgan Meis in The Smart Set:
Kierkegaard was a dissembler and a clown. He had a Christ complex and a club foot. He looked great in an overcoat with a turned-up collar. Much of his adult life was spent mentally obsessing over a woman. Catullus had his Lesbia. Dante had his Beatrice. Petrarch had his Laura. Kierkegaard had his Regine. She appears in some form or another in all of his writing. The reader can be forgiven for not recognizing Regine as Isaac in the biblical story of Abraham and Isaac, but that's the way Kierkegaard saw her.
By all accounts, Kierkegaard and Regine Olsen were genuinely in love. The two were affianced in 1840. But by 1841, Kierkegaard had decided to call it off. Thus begins the great mystery of his life. Why did Kierkegaard choose pain and despair over happiness? The answer, I'm sorry to tell you, is the complete works of Søren Kierkegaard.
Still, we'll try to tease out a few key talking points. Central to the story is faith. Some think of faith as a simple matter — you have it or you don't. For these people, further inquiry is unnecessary. Faith is not accessible to reason. Kierkegaard agrees, a little bit. He never thought that faith could be understood through logic or rational thought. Faith, for him, had to have an element of the absurd or it wouldn't be something special, something outside the normal rules. But he did not think of faith as simple. He saw it as the hardest thing, the greatest challenge, the center of the grand torture we call life. He once said, “If I am capable of grasping God objectively, I do not believe, but precisely because I cannot do this I must believe.”
More here.