Dont know what to do anymore for my bestie

I have known my best fren for a year now. We r bffs initially until her dad died and everything changed. She used to open up to me when she is ready..but besides that she will avoid me also. I find it hurtful and difficult from time to time but i still care and be there for her. I have asked her many times what happened and why. But recently she said not everyone has to be like me . She has her own choice. I think she meant that she doesnt want to tell me. Anyway she has some new friends too and joined back some old friends but I know she isnt okay. She keeps things to herself. I've tried to care but she pushed me away. So now i am cutting her off completely. I feel she wants space. But at the same time i am afraid that i will lose her too. I really dont know what to do anymore.