Was it really me?

I've known her for over 3 years but I feel like we are really close, at least to me. We told each other everything and we supported each other, she was with me when I went through all my low times and ik was there when she came out and her mom didnt accept her. We were inseparable, always together. When she started dating out mutual friend we stayed cool, they never made me feel left out or like a third wheel. Long story short, she broke up with her girlfriend about a week ago and she was very sad. I tried cheering her up and doing everything I could to stay friends with both of them. Three days ago she texted me saying that she's very sorry but that she cant talk to me anymore because I remind her of her ex.

I was hurt, to say the least, she was the first person I trusted and she told me she wouldn't leave me. She knew how I felt about those friendships that aren't true and she promised not to do that to me because she loved me. Was it really my fault? I was just being myself and trying to make her happy. I'm confused on how to think. I'm mad that she broke her promised, but more hurt that she decided to just tell me like that and not even talk to me about it. I feel betrayed and sad, this is why I dont trust people so easily, Will I be able to trust someone again?