No that statement "she is gone just hasn't left yet" is merely speculation. This type of situation doesn't normally end well though, but there could be other reasons. Has she told you why exactly she wants to split her time between both places, have you noticed changes in their frequency of communication and get together, have you noticed changes in her behavior towards you. These are the areas you need to focus on. For me, no I would never move in with another man, that is outside of the scope of the relationship, but maybe there other reasons that you need to find out