You'd best get a prenup! I ain't BSing you neither! If you lay down a big chunk of change to buy her that rock, you should get a prenup that says that you both keep your own shit and if the marriage ends. I'd specify that if it ends before one year, you get that ring back. I shelled out $12K for my wife's ring and she decided she didn't wanted to leave 2 weeks shy of a year into the marriage. I tried to demand that she give the ring back and her argument was that the ring is considered a gift and, legally she doesn't have to give it back. This is true. But I told her it's a matter of principle. $12k for a ring, for a marriage that lasted under 12 months ($1,000/mo), and she is the one who decided to leave. I haven't even finished paying for it. She doesn't give a shit. She's keeping it because she can; she's not giving it back because she doesn't have to. I still haven't finished paying for the fukker. If she could find a way to take my house, she would.
Seriously, I'd get a prenup if I were you. You never know what could happen a year or so from now.