Why do people leave if there spouse is not good in bed?

Because some people put emphasis on the wrong aspects of a relationship. I'm a virgin and I plan to stay so until marriage... while I am a religious person, the main reason behind this is not spiritual in nature, but rather, me just not caring all that much about . I don't doubt that it feels wonderful, I hear about that all the time, but it seems to me that the best relationships are ones where isn't really that big of a deal. I mean, you can have with anyone, literally, anyone, on this Earth, so why would it matter? However, a close interpersonal relationship with someone you trust, care about, love, know much about, get along great with, etc... there are few people in this world you can have that with.