A couple of my coworkers & family members do not have pets. They couldn't believe I was willing to go through the trouble with my cat when he had a urinary tract blockage (apparently they think I should've left him to die)!
Some people just don't understand what it's like to love a pet. They've probably never had an animal in their life... with the exception of that goldfish they won at the fair when they were five

.
One person in particular HATES animals. I wouldn't be surprised if she tries to run over stray cats or something... Her brother brought his dog to her house for about an hour one day and she made him pay to have her carpets cleaned! Can you believe that?!
I was devastated when my lovebird died (he was almost 12 years old!), even though he wasn't an over friendly bird that I could play with, I was still attached to him.
I would ignore their comments. They just don't understand these are our children and that we love and cherish them deeply (they just have a bit more hair!)
Please express my condolances to your aunt. It sounds like she loved her Chi very much. Hopefully in time, she'll be able to open her heart to another one.