[26][16] Let $(X_{t},g_{t})$ be a degenerating family of (polarized) Calabi-Yau 3-folds near the large complex structure limit, equipped with Calabi-Yau metrics $g_{t}$. Then for $|t|\ll 1$, the 3-fold $X_{t}$ admits a special Lagrangian $T^{3}$-fibration over a base $B$ homeomorphic to a 3-sphere, known as the SYZ fibration. The base $B$ is equipped with an affine structure and a compatible metric $g_{B}$ solving the real Monge-Ampère equation with singularities along a trivalent graph $\mathfrak{D}\subset B$, such that the rescaled Calabi-Yau metrics $(X_{t},\text{diam}(g_{t})^{-2}g_{t})$ converge to $(B,g_{B})$ in Gromov-Hausdorff sense as $t\to 0$. Morever, suitably away from $\mathfrak{D}$ the metrics $g_{t}$ are approximated by a semiflat metric up to exponentially small errors.