I believe this is a normal feeling! It is work to keep a marriage together, stable, strong, and comfortable. It takes both parties and sometimes it is great and other times it is 'splitzville'.
Josh - best of luck to you!
My advice - take it or leave it!
1. Try to understand her even when she is being psycho - there is something underneath that she probably doesn't know how to explain.
2. Going through marriage counseling BEFORE the wedding is a great idea. I wish I would have done it - it would have been worth the time and money.
If you are in the Seattle area - try gottman.com.
3. Don't listen to the single bastards on this thread. When you love someone - you will compromise, understand, accept, and LOVE them completely. It ain't easy or always fun - but very rewarding.
CHEERS TO YOU MAN!!!