When modern theologians discuss heaven, they often speculate about the existence or nonexistence of sex there. On the Catholic Answers forum, I read someone declare that if there is no sex in heaven then few people would want to go to there. Honestly, I couldn't care less about conjugal relations in the afterlife.
Now I cannot speak from experience. Between obedience to Church teaching and a lack of social skills, I have managed to remain celibate my entire life. But I do know that the Beatific Vision and the New Jerusalem are going to be way better than the best... um.... marital experiences.
That's not to say that I don't have an opinion on the subject. It seems pretty clear to me that there will be no sex in heaven. In Luke's Gospel Jesus says, "The people of this age marry and are given in marriage. But those who are considered worthy of taking part in that age and in the resurrection from the dead will neither marry nor be given in marriage, and they can no longer die; for they are like the angels." If marriage does not exist it follows that the marriage act won't either. Not that it should matter to us. We should look to heaven with joyful hope, not anxiety about what it is like.