I'm not into gourmet food, but tend to frequent the higher end steakhouses and grills. Here's a few of my favorites:
Baton Rouge- Yes, it's a large chain from Quebec, but the ribs are seriously to die for, your girlfriend (from BC) has probably never heard of it, and it's really close to where you are staying (Albert @ Lyon).
Empire Grill- A bit on the pricey side. Steaks are excellent, decor is unique, and the wine list is second to none IMO. Try the Marynissen Estates Lot 66 (Mick Jagger's favorite Canadian wine). It's on Clarence Street in the market.
Stella- Another Clarence St. restaurant with probably the best location in the city for nightlife. Really good Italian cuisine with yet another great wine list. Try the chicken parmasean.
If she starts to miss Vancouver, try either the Mekong or Hot Peppers (both in Chinatown on Somerset). They are my favorite restaurants for Asian food.
Finally, I have to stand up for my good friend The Works! I love that place and think their burgers are perfect (even the beef ones). Try the Smokey Mountain for a classic taste and add a few sweet potato fries to ensure you get your veggies in.