I think that Grizabella is an old cat who has left the tribe when she 
was young. In her youth she was respected by all the members of the 
tribe but she wanted more. So she left the tribe. I think that she 
got some bad experiences and now as a old cat she returned and want 
to join the tribe again. But the older cats remembered her and 
rejected her until she sings Memory. Victoria and Jemima are the only 
cats who want to accept her immediately.

*purrs*
Meike