Dropping Hints?

I am in a bit of a problem. A year ago my sister in law passed away suddenly leaving my 22 year old niece all on her own with no surviving parents in the picture. She had essentially no one to turn to and because I had a spare bedroom at my apartment and she goes to the college in town I live in she ended up moving in with me. Her and I always had a good relationship as she was growing up and were pretty used to each other so living together hasn't been overall challenging although I noticed recently she has started acting a bit funny. One thing is her wardrobe has really changed over this past year, she used to be a baggy t-shirt and jeans person but suddenly she has been wearing tighter, more revealing clothing that emphasize her curves quite a bit. She also has taken a habit to walk around the apartment in a bra and panties most of the time which has made it a bit hard not to stare at her. The other day I was in the kitchen grabbing something and I had dropped it, she said "here i'll get it." and bent over in front of me, pretty close to my crotch for a few moments. I was absolutely stunned and a bit flustered and when she stood up she laughed and handed me what I had dropped. She also has been making comments here and there about how good looking I am for my age and is surprised I don't have a wife yet. I honestly thought maybe I was reading too much into this until a couple days ago where I had been taking a shower and had just got out. She walked in on me totally naked and i had been so stunned it took me a moment to cover up. She apologized and closed the door and when I went to apologize to her for not locking the bathroom door and her having to see that she said "It was my fault I should've knocked, besides from what I seen you have nothing to apologize for." before looking down at my crotch and patting me on the shoulder.

Is she just overly friendly? I can't lie ever since this has been happening I have been looking at her a lot more and I would be lying if I said she was a beautiful woman and if she hasn't popped in my head a few times while jerking off but it definitely feels weird to think of her like that. I just don't know what to think.