Life on this earth is eating and being eaten. Nothing changes that. This is partially true for us, humans too, because we live in the physical world. People living in todays artificial world (big cities), kept safe and "human" by great efforts, forget this. It is not said in vane: For someone who really knows this world, it is only suffering.
But we have to live in it, because this is also the world we created by our former actions, both in this life and earlier ones.
Liberation or renunciation does not mean non-action. For a liberated soul, his/her actions no longer generate karmic deposites. Of course, this is our ulimate goal, and we might not get there too soon.
What is important is to get rid of attachment. Actions done without attachment don't generate further karma.
So, as a householder, it is ok to have intercourse, if you do it without attachment. It does not depend on your spouse at all. She might attach herself and you still not. That does not mean you don't love her. Because, what is love ? To many times we identify love with attachment. (Think McDonalds and the I'm loving it advertising) Real love is caring not because what you get, but because you see God in the other person. Making love to your wife is serving God. Giving food to your child is serving God. Every action must be done as a service to God. Than they will not harm anyone anymore, including you. Sometimes I say to myself when I lose focus, or I am depressed, or stressed: Why do I worry ? I am not important, these problems are not really problems but only in my mind. Than I feel great relief, and a new power to attend to the things what must be done.
Of course all this is great in theory. It must be realized in our everyday life, day by day, action by action. We might fail a lot, but with every single egoless action, we get closer to freedom.
