When I retired in 2018, a co-worker walked the entire Camino. He asked for walking partners for sections. I (and my brother) walked with him for the section from Saint-Jean-Pied-de-Port France, to Logrono Spain. About 100 miles, including the section over the Pyrenees (rather strenuous for these old bones). It was a wonderful, life changing experience.
I loved the camaraderie of the pilgrims (the nomenclature for those walking the Camino - your neighbor is now a pilgrim). My observation about the demographics - it was mostly dominated by 20-somethings and 60- and 70-somethings. Not much in between for those in mid-career. But I felt like the two ends of the demographic spectrum really added something to each other's experience. I met a 20-something from Brooklyn who walked the entire Camino with his guitar. Had a blast in one of the white towns when nearly everyone on the main square (used mainly for seating for 6-8 restaurants) joined in a hootenany. Particularly a group of rather drunk Irishmen, who were a real hoot.
Also met a 75 year old British gal, who didn't have the oomph to do the entire Camino. So every year, she walked a different section. I think it was her 8th year or so. She was fascinating. BTW, we met at a nunnery, a section of which was turned into an albergue (Spanish for hostel, particularly oriented to Camino Pilgrims).
I'm sure your neighbor will have many fascinating stories when she returns. Kudos to her.