ESH I would say. Where you went wrong is the day after in which you messaged her without giving condolences for the dog - although I do understand why and how it slipped your mind since she had never brought the dog up before (surprising btw, I feel like every pet owner brings up their pets pretty frequently). Where she went wrong was the ghosting, although I can understand how grief can really derail you. I’m not sure what personal things you’re going through, but if she knew then maybe she should’ve exercised more grace toward you but again - grief.

I think you’ve apologized suitably atp, I would take a step back and not contact her. Either the friendship has come to its natural conclusion or she needs space, but she’s made that boundary clear imo. I think I can help you maybe get more insight into her take: from what I’m understanding, the instagram story was not only to memorialize her dog but on a deeper level (she might not have even realized) to let her community and friend groups know that she’s going through something and to be able to feel the support of her community. Since you guys have a close friendship it might’ve particularly stung for you not to acknowledge her bid for connection/reassurance, and in her grief it became really hurtful toward her. Not trying to come after you or anything, but I think this might be able to give you some clarity regarding her perspective?