Welcome to PhotoStructure, @michaelteter !
I haven’t built out secure multi-user sharing in PhotoStructure (but I’m actually currently building it right now, and will be in the next release).
Until I ship that feature, I’m using a “reverse proxy” called Caddy to add https and password-protect the entire library so only my family can view the contents. This setup (and a bunch of alternatives) are written up here:
Feel free to reply here or on discord if you have any questions!