How is she being self important? She was answering a question, and either way a big part of Christianity is about spreading the gospel, because despite what your attitudes are to receiving it, Christians don't want you to have to face eternal suffering.
And sex has nothing to do with the 'meaning' of life. It is a part of life sure, but if you think it will add meaning to your life, then you are mistaken. And yes, sex is a basic instinct and natural, but you're viewing it as if it is solely an act with nothing attached to it (which actually contradicts your thinking that it has anything to do with meaning), but when it is backed by love then it means a whole lot more.