Seconded. My wife has been having this issue for the past two days. Yesterday it was just a specific spot in New Gridania; logging onto my PC and moving her fixed the issue. It was a direct crash to desktop, and she couldn't get past any loading screens.

Today it happened in Limsa Lominsa. I moved her again. We queued for Qitana Ravel, it crashed continually. Now she cannot log in at all.

She has tried using the "Reset" tool in the launcher, and that will work very briefly.
She has swapped from DirectX11 to DirectX9, and still received crashes upon login.

It's worth noting that she has been playing all day on both of these days with no issue, only for the issue to happen suddenly in the evenings with no end in sight.