I'm going to be quite direct. Please don't be offended...
I don't know your fiscal nor your spousal situation. I only know mine. I'm no longer married but if I was I wouldn't hide anything from her. Lack of trust is the number one cause of friction in, and ending of, relationships whether that be financially or fidelity related. Once trust is damaged it never fully recovers.
It's all about compromise from both parties. My marriage was a fiasco. I ended up selling every single thing I enjoyed... my audio equipment, my guns, all my camera gear... everything... because my wife found them inconvenient to her. I bought her many different pricey hobby tools over the years and funded all the materials she needed for them. I had nothing. Above all else I valued being a husband and father but there was virtually nothing else of me left. In retrospect I should have been a stronger man and insisted on compromise.
Hiding things and lying/keeping secrets is not the adult way to handle it. Open dialog and finding a center ground for you "both" to stand on is the only proper option. Find the strength to be a man but don't be an overbearing ogre.
Maybe a bit harsh but truth often is.
I improved on that situation. I traded the wife in and got a girl friend who is much younger, has less mileage and is low maintenance. I have had no problems buying cameras and setting up a darkroom since.
Warning!! Handling a Hasselblad can be harmful to your financial well being!
Nothing beats a great piece of glass!
I leave the digital work for the urologists and proctologists.