Why are you fighting? Answer that, solve why, and work on not falling into that situation again. Talk to her and ask why she is unhappy. Try to fix things with her and don't become another "50% of all marriages end in divorce" statistic.

Consider marriage consuling (sp?).

Talk to your wife, as none of us know what's really bothering her. Only she knows, so ask her and talk with her. If you love her, try and work it out.

Good luck.