Mmm... yes and no. It's more complicated than that. Of course Jedi are allowed to care. It's our-- their job to care. A Jedi respects and treasures life in all it's forms. But it's also their job to remain impartial. That means no attachments. You can't put friends or family or even personal bias before the mission, before greater good. That's why they don't marry, or have family. Why our training starts young, so we don't have any particular loyalty to a home planet.