I don't want my fiance to stay up all night
Why's that? Does she stay up late very often?
Yes, I don't want her to be too tired when she wakes up
If she wants to stay up you should let her. You don't want to come across as controlling.
It's my right to control her. I'm wearing the pants in this relationship.
Is it really your right to tell her what to do? Why do you get that control over her? I think most successful relationships are predicated on there being an equal partnership and I'd hate to see your partner leave you.