Is your spouse/partner bike-curious?

If your wife find the road/lanes too intimidating, you could always suggested cycle training as this is the best way to get her to feel confident and secure on the road, it would make a huge difference and you two will be able to go out on the road more often.

Similarly, keep checking she is ok behind you. I rode off when my girlfriend fell off down the canal into a table of drinks without realising. She was not impressed! to be fair were a mile away from home after 15 and she had been awesome all day so I was a little too relaxed.