[MMM]

I think you are creating a perfect situation to never hear from her again. If she felt strongly toward you, you would know it.

Many women travel outside of Japan to study for short periods of time. They often are not looking to fall in love, but inevitably someone falls in love with them. It doesn't sound like she is fighting to stay in Singapore. That translates to, she is not looking for a serious relationship with you.

If you want to maintain any sort of friendship with her, keep your mouth shut and keep looking.