This squirrel has guts!

I have noticed some interesting behaviour with the local female fox squirrel in my backyard. I attend college, so over thanksgiving break I noticed a squirrel and decided to feed it, since I enjoy feeding the squirrels at school. I had 4 days off for break, and I only fed her for 2 days then stopped, because I didn’t want her to rely on our house as a permanent food source. I returned home for Christmas break on the 14th of December. That afternoon, the same squirrel returned, this time she would come up to the glass of our back door and look inside. I haven’t not fed any animal since returning home nor I even been out in our backyard, and yet she constantly comes up to the door everyday starting at about noon. I have never seen such persistent or bravery before in any wild animal. She isn’t afraid of our dog anymore either. She will usually jump up a tree when we first let our dog out, but then the squirrel makes her way back to the deck, undeterred. I was wondering if you’ve ever heard of this kind of bravery or behaviour from a squirrel before? Or what I should do? I don’t mind having feeding her, but I don’t want her to become reliant on me as a food source, or become violent towards my dog. Thanks for your advice, Jennifer