I'm going to tell my girlfriend that she should stop crying about a dog that died two years ago
Why would you be so mean to your girlfriend?
I just don't see any use in dredging up the past.
If your girlfriend is sad about the loss of a dog, even after years have past, that is not abnormal. It is common to bed sad about the loss of beloved pets. You should show your girlfriend some compassion and understanding instead of telling her to get over it.
Why don't we just stop talking about it?
I'm just saying that it's wrong to not consider her feelings in this. She's not in the wrong here, it's just how she feels.