Let $$ X\,\ :=\,\ [1;2)\ =\ \{x\in\mathbb R: 1\le x< 2)\} $$ The distance in $\ X\ $ is defined by: $$ \forall_{x\ y\in X}\quad d(x\ y)\ :=\ \max(x\ y) $$ This ultra-metric space is discrete hence complete. Also: $$ \forall_{x\in X}\quad \{d(x\ y) : y\in X\}\ =\ [x;2)\ $$ Thus, all three assumptions are satisfied.