Why is my ex still mad at me?

we have been broken up 2 months ago from a serious year long relationship and I broke up with her because we got into a huge argument and I guess the brake up hurt her real bad but about 4 days after the brake up I told her I was sorry and I still loved her I just need a brake well then she told me she was talking to another guy and she didn't know what she wanted well the next day she calls me and tells me she's dating him she ended up meeting him after are brake up a friend of hers introduced them she broke my heart I broke down blah blah blah and from what everyone is telling me he's no prince charming at all like she's buying him drugs but my point is she still talks to my little sister there like best friends but for some reason my sister brought me up and she said she was still mad at me and what I'm wanting to know is if she's really over me and this dude is sweeping her off her feet wouldn't she not care about me like and not go out of her way to avoid me I mean she still has a grudge against me if she was really over wouldn't she be able to face me?