The last panel saved it IMO. They both stopped walking away because they actually need each other and the mere thought of never seeing the other ever again made their body stop.
"Are you seeing someone?" "Yeah" "Me too" : time for sex!
I have a hunch that if one of them was single, it wouldn't have been the same.
It's a twisted relationship, I'll give you that, but who are we to judge? These two women have an unbreakable bond.
Not the kind of relationship I'd seek, but to each their own.