It's not she "needs" to do something, it's what type of person she actually is. She doesn't need to "change" herself in order to "fit" me. Of course, when days pass by, we influence each other and accept each other more and more and will become more "alike". If ones don't feel the love inside, no matter now often you renew the vow won't help the relationship (too 表面 la).
however, even people say they will not leave or cheat on the partners might never know the future.
I think the most important thing is to keep the spark going. It's easy now but how about in 10 or 20 years? I hope my wife can stay the way she is. For me, I will always try something new once awhile to keep the relationship fresh.
No matter what happens, I will never leave my wife first.