A little advice

It's a lifelong companion

It's like if a sibling dies, you don't say "Dude, chill out. They were just a person." We form bonds and connections with anything living, and thus feel saddened when that connection is severed by death.

My cockatoo got attacked by a dog and he got hurt severely. In his last moments I told him that I love him and I will miss him so much, he looked at me and put his head on my chest and passed away. I cried for hours and everyone was like, "Tf is wrong with you? It's just a bird!" :(

I feel like these people either never had a pet or lack a certain amount of empathy

This relates to me on so many levels. My parakeet recently passed away because of some health complications. I was so sure she was getting better, but we later found her on the bottom of her cage, weak and breathing heavily... The last thing I told her was "I'm sorry." I cried for hours and hours on end into the night. decent people like my vet and parents comforted me and told me there was nothing else I could've done, however the girl that tries to convince herself we are best friends just told me that it was a dumb bird anyways and a waste of time, space, and money. (The best part is she has a dog! "But dogs are way different then birds!")

Yep. theres definitely a story behind this one

id rather they say its just a animal so i know just what kind of person they are.

I have a bearded dragon and she came very close to dying a few months ago (she's in tip top health now thank goodness!) But I was crying and super upset and my sisters (who don't share my love of animals) were just like 'um its a lizard who cares'. Just cause it's not a big fluffy dog or a big animal doesn't mean it doesn't mean anything.

Its okay to say it about a dead cow used to make a hamburger, though