Not completely. From the dialogue files I have looked at there are some conversations that occur after the marriage conversations. Using Kira as an example, she has one side quest that only triggers post-class storyline, a dialogue follow up, and I believe a "legacy/children conversation". I haven't beaten the JK class storyline yet though so I don't know if all of those are actually in game yet though.
What level do you get to marry vette? cuz ive got 10000/10000 affection and shes stopped talking.
It isn't level based, it is based on your class story. I assume that marriage dialogues for all characters require you to be in act 3.