Next time you find her sitting on your bench, just go sit on her bench and see what happens. Or if you really want to jump start this relationship with her, then the next time you find her sitting on your bench, walk right up to her and as soon as she stands to move to her bench, throw your arms around her and give her a huge kiss smack dab on the lips. This will, without doubt, either jumpstart your relationship or get you thrown into jail. Either way, you will finally put an end to your anxiety over whether she likes you or not. And you'll do so without even talking to her, which is obviously a plus given the fact you two have an aversion to talking to each other.