Hi Shadix,

Here's my personal opinion on this, although others may differ.

Even if you feel she is ignoring you, just say "Hi" at least when you see her, that way there can be no confusion as to who is ignoring who - you are doing the minimum of acknowledging her presence; whether or not she chooses to respond; this is a matter of her personal decision.

If she in turn acknowledges your presence feel free to have a conversation etc.

And take it from there.