This was flipped for me.

My partner bikes to work in Toronto while I took public transit. I was regularly concerned with her safety as biking through city traffic can get hectic. She encouraged me to bike to work myself and I wanted to but I always feared that traffic.

What helped me? She took me biking along her route and we biked together to her office one monday morning. I saw what the conditions were like and it calmed my nerves. Instead of envisioning her weaving through traffic, I saw her, and road with her on calm side streets all the way to work.

She has also done a few things that steadied my nerves, such as use some fancy lights I bought for her bike.

Would your spouse be up for a bike? Would taking her along your route be something that might calm her nerves?