Re: to date your husband?!
There is no religious reason to not hang out and get to know one another after your Nikkah, so your mom is def wrong about that. However I can definitely understand her concerns if you made it a stipulation in your Nikkah contract or something that you will not give each other husband/wife rights until rukhsati.
Mostly desi parents dont want you guys hanging out alone because its harder to control yourself around one another after nikkah, and plus you know desi people, if they see you two out together even though you are married, but they werent invited or they dont know about when your rukhsati is, log baatein banaate hain, etc. You know how it is :o