thank you for sharing your sitaution with us in the community.
As for your questions:
1. As you wont have alegal status if you withdraw your asylum case, it is best to do it once you are married, then anyways your status will change through marriage.
2. No legally it wont make a difference, however Italy has a more rigid policy towards asylum seekers so they might make it harder for you, therefore it would be good to get the assistance of an attorney/lawyer.
I hope this could help you, if you need further assistance please do not hesitate to reach out to us.