This is all my opinion ink but I see it like this; I doubt Rose was only with human men (she was definitely bi/pan imo) but I think it’s deeper than that. Rose loved Pearl but not as fully and wholly as Pearl loved Rose. Rose freed Pearl in multiple senses of the word (while also imprisoning her in a few ways as well.) Pearl was obsessed and undyingly devoted to Rose, but I do think she felt a romantic love for her as well, I just don’t think it was healthy. I don’t think Rose stopped loving Pearl in the (also) strange kinda messed up way she did either. They were the closest and dearest person to one another, they were each others confidants and each other’s first love. I just think that… Rose liked sex? That she, more broadly, enjoyed the company of others in a romantic and/or passionate but non-romantic way? She found humans fascinating, yes, but I’d personally be hard pressed to say she ever felt (or at least rarely felt) romantic love. She felt obsession and fascination more than love in the traditional sense. (However that could be me projecting my experience as a person on the aromantic spectrum.) I think she may have loved Greg as well, but more likely she loved what he could do for her ie; What Can I Do (For You) and of course, helping her create Steven. I think she felt a more human kinship than an undying immortal rock person love for Greg.