It's all very well talking about how you abandon hierarchical relationship structures and the like but when you completely ignore the fact that people have joint responsibilities that create obligations and are a priority. That isn't privileging a relationship, it's taking care of your shit. Once you have formed these obligations and responsibilities, you can't just take this hippyish approach suggested where relationships are fluid and change and you just have to go with the flow. No, those responsibilities always come first.
If you truly abandon hierarchical relationship structures, you would not share a home or any other financial responsibilities with a partner because of the inherent priority those obligations take over everything else. But living with someone you love is awesome, so why not stop being so adamant about abandoning hierarchy, and admit that you prioritise your obligations rather than people. That does mean a lot of the time, things that involve the person/people you live with and the children you raise will come first simply because of the obligation, not because you love that partner or those partners' more, but really, that is just practical and how life works.