Here is a shower made with couples in mind. Boona’s Tandem Shower ensures both users stay warms, so no reason to struggle to switch sides. It uses an insulated hose to make sure you get the same temperature out of each showerhead.
Tandem Shower offers 3 different settings. It also saves water in comparison to using two separate showers. Its flexible hose lets you install it with plenty of clearance. Like what you see? You can find this project on Kickstarter.