She may regret her decision not to date you now that she realizes that someone else has you.
This is human nature.
We are often blind to what we have until we lose it.
This may be what has occurred in your situation.
She may have realized that she should have taken you on your offer or given you more of a chance.
This is especially true if she notices how happy this person you are now seeing appears to be with you.
She may now want that kind of happiness and may be envious that she isn’t getting it.
As I stated earlier, as human beings, we often take what we have for granted until we lose it.
She may have believed that you would continue fawning over her and trying to pursue her.
She may have really enjoyed the compliments you were giving her or how hard you were trying to pursue her.
She may have really loved this kind of attention.
However, now that you have directed that energy and interest to someone else, she misses it.
She may now realize that she wants it back.
She misses the fact that you used to look at her so often.
She misses the fact that you no longer try to talk to her or give her compliments.
She may even miss how you used to try to make her smile by telling jokes that may or may not have been funny.
That attention is now gone because you are focused on giving it to this new person that you are dating.
She may miss that attention.
As a result, she wants to date you even though she made you believe that she didn’t in the past or made it way too difficult for you to do.
Now, everything has changed because there is someone else that appears to be happy and is also garnering the kind of attention that you used to give her.
She may also want to date you now that you are seeing someone else because she may believe that the person you are dating isn’t better than her.
She may truly believe that she has a lot more to offer you than this other person does.
This may be a person she may not even particularly like.
She may believe that this person is actually not on par with her own beauty or social credentials.
Perhaps she feels somewhat slighted that you would date this other person who is so obviously not up to her level.
There may be a competitive side of her that believes that you have taken a step down in dating this girl.
She may want to correct that because she believes that she is better than this girl.
She may believe that she would be a better match for you on every scale from her physical appearance to her social status.
This is the competitive kind of mindset that girls often have when it comes to dating.
They may make very little effort with a guy who has been pursuing them until he moves on to another girl.
All of a sudden, they feel competitive and realize that they are better for the guy than who he has chosen.
This competitive mindset makes them change their mind about the guy and now they want to date him.