Some women are not ready for the rigors of pole dancing. Even the mid-level techniques takes a certain level of muscularity and unheaviness that some women haven't achieved. Perhaps have her start on something that is easier to get into, like nude yoga? There will be little up front cost, and she can invite some of the ladies from the neighborhood over to the house to do it with her. Now, one word of advice: there is a ton of misinformation on the internet about yoga making you "long and lean" and stuff like that, so if she reads that stuff by all means encourage her, and don't let more factual information get in the way.
I would be willing to waive my normal fee and give your wife advice, just have her email me pics of the yoga sessions. Good luck!