The thing is that our bodies determine the processes that occur in our mind. There is even a special branch in psychology dedicated to the studies of how changes in the body affect the mind - the so-called somatic psychology. When we artificially change the facial expression according to a particular emotion, after a short time in our mind appears that particular emotion.
Numerous laboratory studies show that people who were asked to lift the corners of the mouth and keep them in that position for some time, really get the feeling of joy. By the way, with such a scheme, you can wean yourself permanently to feel a sense of disgust. Try to imagine what is causing this feeling and observe your facial expressions - usually the mouth corners fall down, the nose is wrinkled, eyes are squint. That is, the sensory organs (eyes, nose, mouth) become smaller as to isolate themselves from sight and smell of the stimulus. But if you control your facial expressions, and your face will retain its usual expression with the appearance of the stimulus, then it will disappear the feeling of disgust.
Here is an example directly related to our theme: a well-known exercise: when a woman learns to experience an orgasm, she tries to imitate the facial expression and gesture of it, and with some skill, it all ends with the real orgasm itself!
Of course, during times of stress, the "sexual mood" is rarely good, so do not wait for its arrival. The main thing is to make the first step towards each other. Everything else will come. Or rather, can come - because everything depends on you two. When making love, not just fulfilling the conjugal duty, we find ourselves in another world, and in this world- there is no stress, no thoughts about work. There's nothing at all. Unfortunately, for a modern man, it's hard to get into this world, and even in bed, he drags with him lots of ideas and issues. How to get rid of it? There are plenty of exercises that allow to overcome this barrier. They can be found in appropriate books, which have recently appeared quite a lot. In addition, in the big cities there are trainings that allow to combine well the theory with practice.