Hi Charleene,
You are about in the same time period as my husband when he started CDing, (more than 35 years after we were married). After being married so long, it was definitely a big surprise (to say the least). We had our ups and downs, there was definitely a learning curve, but I would highly recommend not hiding this from your wife. Please re-read Reine's post about what not to do because if you start down this road, your wife is bound to find out sooner or later.
from Reine:
Your best recourse is to just be honest. Also, a degree of flexibility is best. The two of you might need to negotiate what she sees and how often you dress.