Wow punkrokchk2000, if you're looking for piece of mind, don't read my thread
I work 6am 'till 2:30pm. GF works 4pm 'till 12:30am(or later). It's tough. Some people enjoy the freedom. I don't. However, I don't know your situation. My GF's got a son who I take care of in the evenings. I think it'd be much easier if I didn't have that responsibility.
However, many people do it and have wonderful relationships. It'll take some adjusting for the both of you, but i'm sure it'll work out fine. Good luck.