I personally think this is more common than some people want to admit. People get home frome work, take care of dinner and kids, clean up the kitchen, then it's maybe, what, 830? They're really tired, probably most days. Last thing they feel probably is sexy. They want to put on jammies and snuggle with the doggie and a soft blanket and some tea. Not get into a wrestling match. I totally get it. Things are a lot different when one is in their early 20s, say, and there are no children. Even if there are no kids at all ever, as mentioned, some people just aren't that into it. There's nothing wrong with you.