Kat,
I know that it is nice to be able to stay home with your children. My wife and I decided she would stay at home for awhile with our little girl, who is now 2 and half.
Like you my wife is torn on the decision to work or stay home. I try to support her in whatever her decision is. She has decided to work part time, in the mean-time she is developing her own interior design business. Not only does she need to do this for her own personal sanity, but for the development of our daughter as well. We want her to have the social interaction with other children and be able to be away from mom and dad for awhile without major stress for her.
There are times when I am both thankful I can get away to work and envious, because I would also enjoy the "Mr. Mom" role to soem degree.
Through all of this you have to keep in mind that it is your life and your decision. You need may need support and/or help, but not a hinderance. While it may be difficult to do this, you may feel better in the long run...to do what you think is best. Period.
Hang in there......