With a tourist guidebook in hand, Joséphine, 30, marveled at the photos of vineyards and the sweeping landscapes of the Douro Valley in Portugal. Next to her, her partner sighed. He would have preferred to wander the streets of Porto. "Yet the Douro Valley was his idea in the first place! But he always found a way to contradict me and stay in control of the itinerary," joked the physiotherapist, who lives in Wallonia, Belgium.

Usually passionate about excursions and discovery, the 30-year-old gave up on organizing anything and turned inward. Her boyfriend stayed sprawled on the couch of their rental house, absorbed in a TV series; so much for the fado concert she had so carefully chosen. "Before we left, I could already tell he needed to be in control, but once we arrived, it got even worse!" recalled Joséphine, who had been in the relationship for four months at that point.

During that weeklong vacation in April, the couple struggled, and arguments flared between selfies. Halfway through, they tried to salvage things: a conversation on the terrace, a few concessions made on both sides. Joséphine tried to calm things down, willing to set aside her own wishes to preserve their partnership. But on the way home, stuck in their air-conditioned SUV between backpacks and unspoken words, one final argument erupted. Their story ended at a highway rest stop, between a snack machine and public toilets: "We still had four hours left to drive... It was a bit tense." That trip showed her a partner who was quick-tempered and unable to let go.

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