My experiences of loss
I've added a special page on here specific to pet loss as I feel that it's an isolating experience that people suffer and don't always feel validated in seeking help with grief of a pet.
I wholeheartedly understand the impact this has.
Some of the differences I've noted when losing loved ones; when it's a person, people say "It gets better with time", "They're in a better place now". When it's a pet, people say "Are you going to get another", " Do you want a cat/rabbit/fish, I know someone that's rehoming one"
None of the above are helpful or supportive. They're dismissive of the pain you're suffering and suggest time or a replacement will heal your grief. They don't.
Seeking the support of a bereavement counsellor will provide a supportive space where your feelings are heard and understood, never rushed. Where you can explore the changes you now face and the impact on your life moving forward.
This is to by no measure to compare any losses as being the same, but to acknowledge all losses are painful to a person grieving.
All grief is valid, it's the measure of the love you had for who you have lost.
Things that may help to show understanding
It's ok to not know what to say or do to support someone when they are going through grief and bereavement but it's important to acknowledge it. Even if it is to simply say "I'm sorry for your loss", "I know words won't help right now".
The kindest thing you can do for someone, is show that you remember too, because for the person grieving who may look like they're holding it together, they're probably just wearing a mask so other people don't feel uncomfortable in not knowing what to say.
Sharing memories with a grieving person or acknowledging the love or bond you know they shared can help.