I guess only a couple of people will ever know the answer to that, but as I don't share the distaste of others for the tabloid aspect of footy so I'll give you my theory on what happened, and it is just a theory.
The affair started no later than early 2019 and probably much earlier. Hardwick informed his wife of his decision to seperate during the shutdown in 2020. She travelled to the hub still hoping to reconcile and was made aware that Hardwick intended to move on with a new partner, and quickly left again. Ms Crow then also left her partner and travelled to the hub, and from that point they have been together.