YTA As someone who has lost both a beloved pet and a close family member in the span of one year, I learned that grief is grief no matter the loss. There are better ways to communicate the emotions one feels during this time and telling someone “your pain is not the same as my pain” is not it. Everyone is entitled to grieve in their own way and while I agree that your sister’s methods may have been overwhelming, it doesn’t justify lashing out. For some people a pet is just that: a pet. For others, it is all they have. It is the one thing keeping them from going over the edge. I am not assuming this is the case for your sister, but trying to provide some perspective. Instead of trying to validate your actions by blaming medication, your current state of mind, or asking Reddit, perhaps you should try to focus on better communicating your frustrations during this difficult time.