So maybe this will be considered "cold" advice, but hear me out.

My ex was a pro a baiting me with little things like this, and it went on for years. Looking back, I realize it was just a weird form of emotional manipulation. The tactic of teasing something clearly drastic and negative for you, and then deliberately choosing to not be transparent is either incredibly immature, or intentionally manipulative.

If it was something terrible (like a terminal illness) that she didn't want you to know about --REALLY didn't want you to know about-- she'd not tease it. But baiting you to make you worry, then closing up... that's all about attention and puts her in control and you as an emotional dependent.

My advice: tell her since she'll be gone in a year, you've decided it's time to move on and break up with her so she can settle whatever it is she is dealing with.