Do I have a right to cry about this?

I had been so down lately then all of the sudden I was on a walk when I saw this little scrawny skinny ugly looking black lab. So I took her home and fixed her up. Now she is gorgeous and I knew I was never going to get to keep her but it's been a week and she is like my child she follows me every where and I love her so much. My parents decided to give her to my sister who lives 45 minutes away. She is picking her up tomorrow. I can't stop crying although I don't feel to sad I know she is going to a good home? Do I even have a right to cry about this am I just being a pansy?