Perhaps the answer is as simple as an extension for you to work in, which is set up as an airlock-style system of doors, so that you are not really disturbable

Perhaps the answer is as simple as an extension for you to work in, which is set up as an airlock-style system of doors, so that you are not really disturbable by your wife. I mean simply three or more doors in a row, with a little gap between each. A den, if you prefer. Or an inner sanctum. It is at least worth a good try.