The number one thing should be that you make sure that you ride with her, and let her help choose the distance and pace, and fast or slow doesn't matter. Perhaps try some day trips and training rides before trying an overnight ride.
Organized cycling events might be fun, but alas, not necessarily practical this spring/summer.
If she isn't riding, or only rides a "cruiser", then bike choice might be tricky. One bike? Multiple bikes? Road, commuting, gravel, do-all, ???
Try to get her onto a similar style/quality bike to what you'll be riding. Don't head off on a carbon road bike and give her a MTB. If there are differences in strength and endurance, cargo doesn't have to be evenly distributed, or even distributed at all.