What a fascinating conversation.
Snotty, am I right in understanding that a large part of the issue about the premarital sex is because you are very opposed to having an exnuptial child, and so you are using NFP? And that's making you feel guilty? So that, in fact, the horse is not out of the barn sexually speaking, because according to your faith, every time you have sexual intercourse using the NFP method it is an occasion of sin?
Because that makes perfect sense to me. I mean, I'm an atheist with huge philosophical and feminist objections to the Catholic church, but it is a consistent religious position. You are continuing to sin every time you have intercourse and deliberately avoid getting pregnant, and you can't get pregnant without a church marriage. Right?
But then there's the goalpost moving. And the temptation aspect. And you and your partner clearly love each other and are deeply committed.
The bit that I don't understand, really, and a lot of others don't either, is that you didn't ever jump into bed lightly; the physical side of it came only after you already made a serious commitment to one another and you obviously thought hard about it. You're both religious. You've moved heaven and ear...sorry, I mean, you've gone to a lot of effort to be able to marry, including finding a priest who would be willing to grant an annulment.
And you say that the relationship is important enough to you that you will compromise your religious beliefs about the sex issue rather than lose your partner.
And yet, you won't move the wedding forward. Because you're still 'growing as a person' - but you sound like you're growing towards a - for lack of a better term - conservative religious position, such that surely marrying in the eyes of the church as soon as possible is the only consistent position? Because of your partner's grieving - but taking away the comfort and warmth of your physical self isn't exactly helping there. Because of the logistics of the venue - but that's silly, you can surely get your priest to marry you in a quiet ceremony now and then reaffirm your vows at a later date?
It's the reluctance to move forward the ceremony that's making several of us wonder if there's something deeper going on, whether your spiritual path is making you wonder if you want to be married at all (you're not thinking of a spiritual vocation, are you?), if there's something else going on that we - or you - haven't got at yet.
Because I can absolutely see your partner being supportive of the religious conviction aspect. But not if you're also not willing to move forward the date. You can't escape the fact that you're saying to him 'I no longer wish to have sex with you until marriage, and I have no desire to do anything to shorten the time until then'. It's the second half that's the killer.
Good luck, though, OP. I hope your talk goes well.