relationship stuff
As many newer books as there are on this, I recommend The Ethical Slut by Dossie Easton and Janet Hardy for being staunchly feminist without being overbearingly lib-brained. Other books will teach you how to shop around, more or less, but The Ethical Slut is about being completely and politically in love. That said, it was written a few decades ago, so it can seem a touch outdated in basic terinology, but the authors don't make an effort to exclude anyone and the advice is often applicable to anyone. More modern books can feel a bit geared to cis/straight couples and their proliclivities and relationship styles in the dating scene despite trying to be inclusive.
I would also recommend The Communism of Love by Richard Gilman-Opalsky. It's not really a book about dating and is moreso a book about understanding human relationships under capitalism, but the topics can be generally applied to polyamory given that it consists of human relationships. The author is an American college professor so his takes on communism are colored a bit by that, but generally his feelings on how communism relates to relationships hold a lot of water. It's good for being able to name your emotions when it comes to being part of a community.
A good list of definitions you'll see often in modern poly circles.
What you seem to be talking about might be platonic or queerplatonic relationships, which is rather normal. But just to clear it up, is the relationship between you and your partner romantic without the sexual component or are you two in a sexual relationship while it's expected that your other partners will be romantic only?
You would think so until you find out about the incel-to-trans pipeline and see some absolutely unhinged chan rants about the superiority of the submissive qt trans tradfem.