God Bless you!! You did a wonderful job! She now knows what it's like to be loved..... something she never knew before, and had it not been for you, she would have died never knowing, even though she never acted like she cared, or knew what it ment to be loved, that's irrelevant.... the fact it that you loved her is all that matters!
As for not being with her..... don't feel bad, you'll always be with her!!