I understand the paradox I think you feel you are in:

On one hand, she COULD be right... because people are people.

On another hand, how can she predict the future?

On yet another hand, how can you express that to her in a way that she won't feel you are just pressuring or attempting to manipulate her...

And yet another hand that you can't SHOW her if she's not open to it...

So, IDK...

what's 3 or 4 more months to SHOW her... without her having to commit to it...?

And how WOULD you SHOW her?