Kant has a lovely thing called the "Categorical Imperative". I'm sure I have the exact quote lying around in one of my books somewhere, but I'm going to paraphrase him (glancing around at bookshelves to see if the anthology I'm thinking of is within easy reach . . . doesn't appear to be. Paraphrase it is). His Categorical Imperative states that individuals should always be treated as ends in themselves and never as a means to an end and that when deciding whether or not an action is moral, one should consider whether it is universally applicable or not. Kant was rather stringent in his application of the imperative; he was wary of stepping outside the boundaries that he believed his imperative set. From this stringency came a profound sense of duty to others.
Learning my philosophy at a religious institution as I did, Kant's imperative was a convenient co-opt of the Golden Rule (which we all knew Jesus had come up with first, regardless of the fact that the Buddha and other proponents of the rule had lived hundreds of years before him). We commended Kant on his ability to rationally necessitate the Golden Rule; we were down right smug, I think.
However, not only did Kant give us philosophically sound ground for being Christian, he also provided me personally with a reason to stay in what was a very . . . difficult, conflicted place, id est my marriage (which I had entered into before studying philosophy, btw). Not only did being Mormon-Christian require one to live the Golden Rule, but it also required one to live the commandments. My impression of the commandments at the time was skewed by well meaning but misogynistic religion professors who managed to turn even the parable of the talents into an admonishment to get married and have lots of children. Well, I had gotten married and had a child up to that point, but it had all been under severe cultural pressure. My husband's and my relationship had consisted of making out in the back of my car and talking about whether or not we should get married. I felt like I had a duty to marry this apparently righteous priesthood holder and so I did (although I look back now and see that I was actually going against Kant's ideas of treating him as an end rather than as a means to an end). After I got married, I realized that I really had nothing in common spiritually, intellectually or emotionally with my husband. However, in Mormonism, short of abuse or adultery, divorce is frowned on. Plus, I'd had a child with this man and that increased the amount of duty I felt in staying with him (if for no other reason than out of duty to the child to be raised in a two-parent home). It's amazing that in our co-opting of Kant's imperative, we had managed to twist it to the point that we actually were using others as a means to our own purported salvation (but we were doing it out of duty, by god!).
Now let's talk about Nietzsche. How do I describe Nietzsche? The Nietzsche that you learn about in undergraduate philosophy classes is famous for his Will to Power. At my school, his was a dangerous school of thought. He was blamed for everything from the Nazi invasion to our modern materialistic culture. His Will to Power asserted that the Christian ethic of pity and charity was weak and prevented humanity from reaching it's full potential. If you give to your neighbor, don't do it out of smug superiority but out of a sheer excess of your own power. Do it because you are a truly great human and that's just what great humans do. At the same time, though, Nietzsche advocated for a tantalizingly individualistic world view. For Nietzsche, the only authority that one need consult was oneself. I still remember walking out of my class the day we read excerpts from his "Thus Spoke Zarathustra" being changed forever. At the time, he was like a revelation from God. Nietzsche offered me the philosophical permission to make my life what I wanted it to be. He freed me from listening to outside voices like prophets and apostles. I think a part of me knew even then that reading Nietzsche had given me permission to leave my marriage.
My marriage wasn't what I wanted out of life. I had wanted to go to graduate school and immerse myself in academia (originally I had wanted to do comparative linguistics, but I fell in love with philosophy and changed my mind). My mother had told me that I couldn't have a career and be a good mother and so I had decided I just wouldn't get married and have kids. When I was in high school, this seemed like a good idea. But I had also internalized the idea that the prophets knew what was best for my life, and so when I was told that my life's work was to get married and have babies, I decided to do it and give up my career ambitions. After all, it was clearly what God wanted me to do.
The Kantian model was enough to keep me in my marriage until I realized at some point that I was simply making myself into a means for other people's ends. Also, as I lost my belief in an afterlife, I realized that I only had one shot at life--if I was going to do anything, I had to do it now and chances are I'd have to do it by myself. Finally, I got up the courage to switch my morality. I work from the Nietzschean Will to Power. Is it easy? No. Does it hurt sometimes? Yes. Is it fun hurting other people? No. But ultimately, I was hurting so badly by hanging on to the vestiges of duty bound morality that I knew I had to give myself permission to live for me. And so here I am. A little lonely from time to time, but lonely on my own terms. And for now, that makes all the difference.