My observation is that in regular social life there is really only one thing going on. People want to get paired up, have access to sex and the comfort of sex and friendship. Once that is in place, all other relationships are of less or even worse, have no importance to them at all.
I think it is probably biological, that is the arrangement is based on the need to actually procreate in suitable circumstance.. and nothing wrong with that! But also I think it is the need for companionship in a socially limited and dysfunctional world. I think this is what is going on and it is hard to deny it or say it is wrong.
But the social behaviors and conventions are certainly a limit on energy and potential. I think that a “spiritual” life requires that we understand this limit on life and intimacy and go beyond “the cult of pairs,” so that our intimacy is not confined to a certain direction but extends to everyOne and everything everywhere in the One absolute condition of Reality in which all others and every “thing” is happening. Not that we should abandon exclusive sex relationship, because any other form other than monogamy is generally socially dysfunctional, but to understand with your partner what the problem of the cult of pairs is, and allow each other to be turned outward into all relationship with all and every body else. How wonderful to have each other AND have everyOne else as well.
You will allow each other autonomy and develop personal interest and close friendships with a range of people, each in your chosen directions. Partnership is a matter of choosing each other freely and enjoying wonderful time together, shared interests of every kind and body intimacy.
But it is not a substitute for the total connection to Reality (that which beats the heart and moves the breath and sex) or an attempt to find it with each other exclusive of all other connections. It is a opportunity to feel and express that Reality connection together and to extend the enjoyment felt in your “principle” relationship to all other relationships.
Enjoy your principle relationship with a frequency you both agree upon while extending your love regard to the whole world. The power of your partnership will “fuel” your commitment to all others.
The autonomy of your daily yoga practice goes a long way to ensure that you feel intimacy with life itself that is then felt in and as all relationship, no longer trying to grasp it in your partner or in “things” in limiting co dependence.