Sorry if this is a little late, and that the message might not be of any importance now, but here is what i have come to (and I'm sad to say it's not much):
The format that the text is in is 16 characters on each line, we can make one assumption...
The Cipher could be contained within a 4x4 grid, and in that case would most likely be a Route Cipher.
But we cannot get anywhere without a Key.
The encrypted text you have given does use several uses of the letter "J" which does not make any sense, because often "J" and "I" are substituted for one another and the "I" is most commonly used when it is substituted.
This means that either your Fiancée is either very clever or it is not a Route Cipher. This would be much easier with a key of some sorts, but without the text is pretty much useless.