Give her time. Cats prefer routine, and just because this kitty enjoyed lap sitting with her former owner doesn’t mean she’ll automatically transfer that affection to you. Affection and friendship take time to develop.
She first needs to know that you are not scary. The fact that you fill her food bowl helps with that, of course. But also find a pastime that she enjoys (perhaps chasing a feather toy?) and indulge her. Before she’ll seek you out she needs to discover for herself that all kinds of wonderful benefits happen near you.
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