While I agree with your statement that 'love' cannot be divided, that a person can love, ie, feel the emotion of love, equally strongly for two or more people, we can't separate that in practice from what it is to be involved with someone who is giving half their time and resources to another.
We can argue till we're blue in the faces if it's a societal construct for a person to expect more time and resources from another. It's beside the point The OP wants more. Most people will want more.
You want more. You tried polyamory, briefly, felt mistreated and gave up on it. I still disagree "most people would want more," ie: more time and resources from a partner.
In monogamist culture, if you live with one romantic partner, day in day out, for decades, you begin, in many if not most cases, to take them for granted. While perhaps trying to suppress it, our mind and desires wander to fantasies of relating romantically and sexually to others. You mentally undress and fuck people you see on the street. You read romantic literature, or erotica, follow and discuss the love lives of celebrities, watch romantic comedies, read about the love lives of kings and queens and nobility and villians of history (or TV shows or movies about them), watch porn, etc. You fantasize about being polysexual or polyromantic. This can not be denied. Romance novels and movies and TV shows, erotica, celebrity magazines and websites, pornography for sale or for free now on the internet, are hugely popular.
So much for monogamy! It's not real. It's just a convenient way to hold society together, all based on the legally married hetero male/female lifelong pair bonding, which is a basic way to ensure the success of raising the next generation of humans, to ensure the survival of the species.
There are other ways to raise children not based on monogamy. It can be argued that tribal life is actually a safer more stable way to protect children (because of multiple adults being responsible for all the children), and it has only been left behind because of economics causing the growth of cities, the dissolving of tribes, etc., etc.
Monogamy (or polygyny as it was in Biblical times) is also based on a patriarchal society, where men rule over women.
We all share our love with many, if we are healthy members of society. Putting all your love eggs into one basket, all focused on one other person in a claustrophobic monogamy, is detrimental to emotional growth and health. It's better to accept that many people in your lifetime will love you, and you will love them. Or you end up like Michael Pence (our VP), who can't even be alone in a room with a woman other than his wife-- which is laughable!
Some women are so dependent on their one man, they will neglect their children in order to put his needs first, as if he is on a pedestal. Some counselors (religious or secular) still recommend this. They'll tell you to neglect the children if the man needs to have sex, for example. Let a baby cry, let a distressed child be locked out of the bedroom, because the man's need for sexual release is paramount. His "need" for an orgasm in a vagina trumps all other humans' needs.
Let's face it, you will love several romantic/sexual partners over a lifetime. Sometimes more than one at a time. You will also love your platonic friends, your parents, siblings, grandparents, other relatives. You will care for your colleagues. You might be a doctor, nurse, teacher, minister, and love your students, parishioners or patients. All these people need some of your time. If you have beloved animal companions, they also deserve your time, for care, for exercise.
So to quibble about time percentages (he gets X%, she gets XX%, he gives more percent of time than she does, etc.) is ridiculous. We all work out how to share our time with all our loved ones, relatives, friends, students, pets. We also must love ourselves with a good dose of me-time for self care, or we become martyrs.
I assert that giving 100% of our time to one partner for life is an unhealthy expectation or obsession. It can lead to self-subsumation in a relationship, where we lose all sense of our individuality and become ill with co-dependence, where we can't make a move as an individual, because our one partner owns us; everything must be done as a couple, or extreme distress in the form of jealousy taints our lives.
Of course nobody can give 100% of their time to another. They have to eat, sleep, go to work, coach little league or go to play practice. Maybe they have 50% of the pie left after all of that.
A poly person, however, has to do the same things--eat, sleep, work, other activities. Their 50% of the pie to give to a partner must now be divided between two. Therefore, each partner is getting 25%. Add a third partner as some have, and each partner is now getting about 18%.
I assert that giving smaller percentages of time to others is healthier than expecting one love object to give 100% of time left after work, eat, sleep, etc.
For an example, my live in partner Pixi is a camp director. For about 10 years, as a counselor and now director, she has spent the entire summer working at a camp for kids with special needs. I have no problem having her gone all summer. I know those kids need her love and direction and encouragement. She also needs to love children and can't have kids of her own. And she grows being loved and respected by her colleagues on the leadership team at camp. And by mentoring young counselors.
On my end, we are very much together most of the year, the other three quarters. So, I don't mind when she's gone in the summer. I get more me time. I get to watch the TV shows and movies I like that she might not like as much. I can read more. I get to spend time with friends. I get more sleep. I have less cooking and dishes to do, less clutter around the house. It's just more peaceful in general!
And when she does return, absence has made our hearts grow fonder, and we reconnect madly, and appreciate each other more after the break. We never take each other for granted.
And our relationship is further protected by our polyamory. Our other lovers/partners/sweeties provide a thing or two we can't give each other, so we are not tempted to stray and cheat to get those needs met.
I suppose we could work on changing society to accept a 'construct' that thinks 18% or 25% is fine. But why would we do that?
Because it may actually be a healthier and more honest way to live.
