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The Thermodynamics of Love

Is your relationship stable? Consider its chemistry

There’s a man with whom I often dine though rarely speak. He’s part of a Sunday dinner group I’ve been attending off and on for nearly eighteen years. It started when we all began having children and needed time together, and many bottles of wine, to decompress and celebrate having survived another week.

This man – a father of three – is tall and quiet, a beanpole Buddha with a Mona Lisa smile. When he does speak, I’ve learned to listen. Recently, he sparked a conversation that still has me contemplating his metaphor. He said it was a theory he formulated during college while observing his friends in their early attempts at romantic relationships.

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“The semester I was taking a class on thermodynamics I started looking at these couples from the standpoint of chemistry. The way you decide if you’ve got a good thing going is to figure out if the relationship is mostly endothermic or exothermic.”

He went on to explain, as we all scoured our academic memories for the difference between the two, that if you’re needing to continually feed your relationship energy, it’s going to eventually burn out. You will deplete your source of fuel and the reaction won’t provide you any with anything of substance on which to thrive, let alone survive. If your relationship is exothermic, it’s an energy producer, the good kind that makes you feel topped up. This, he said, became the only advice he gave his friends when they complained about their relationship difficulties.

I immediately had a vision of myself and an old boyfriend arguing vigorously while all the energy around us, in the form of a malodorous vapor, was sucked into our screaming mouths. We vibrated and gesticulated until all the vapor had been consumed, at which point we both deflated. And that was the end of us. This is about the way things played out in real life, it just took much longer.

I piped up. “So how many of you in past long-term relationships stuck with the endothermic kind longer than you should have?” Nearly all of us nodded. I turned to look at the man I had just started to date and he smiled. We’d both seen our previous relationships become energy sucking. We also knew we were presently in an undeniable state of exothermic bliss. Would our current chemical reaction prove temporary or would it continue to generate all the fuel we needed to be happy?

Having been raised by a well meaning, psychotherapist mother, I was conditioned from an early age to believe that relationships require work, sometimes quite a lot of it. But when things felt rather shitty with the man I was trying to ‘work on it’ with, I began to question just how much work any relationship should require of us. So often wrung out from arguments, just what did I think was going to change the chemistry of our particular experiment? If I’d considered the net energy gain or loss of the relationship earlier, might I have saved myself a lot of grief?

Later, I looked up the literal definition of endothermic and exothermic reactions. And just for kicks, I substituted ‘relationship’ for ‘chemical reaction.’ (words in parentheses are mine).

“A chemical reaction (relationship) can be considered a system. A c.r. (relationship) is a process, where one or more compounds (individuals) are converted to a new set of compounds through a series of changes. When the c.r. (relationship) proceeds, there can be a heat transfer from the surroundings to the system or vice versa. Endothermic c.r.’s (relationships) are a process in which energy is acquired from their surrounding to the system, while exothermic (relationships) are processes that release energy from the system to the surroundings.”

Granted, an exothermic reaction includes nuclear fission, highly unstable if not contained. And baking bread is endothermic, something I would rank as soothing and a lovely thing to do for your mate. But stay with me; the metaphor will work if you consider these reactions further:

“In endothermic c.r.’s (relationships) the products have a higher energy compared to the energy of the reactants (the individuals). Therefore, products are less stable than the reactants. (For example, bread will spoil quickly after its ingredients are combined). In exothermic reactions, the products are more stable than the reactants because their energy is lower than the reactants’ energy.” (The energy released after nuclear fission is awesome but the molecules involved are more stable after they’ve split.)

So, if we are the reactants, an endothermic relationship creates a product that is less stable than the compounds that produced it. We’ve all felt a little crazy around certain people, and more capable and even-keeled after removing ourselves from their influence. In contrast, an exothermic partnership produces love energy and makes potentially unstable reactants more stable. This is the contentment (good energy) otherwise anxious people can feel with people who calm them.

In psychology there’s a term called ‘emotional co-regulation’ which could be (for the purposes of my theory, anyway) be considered the equivalent of an exothermic relationship. Emotional co-regulation is defined as “a bidirectional linkage of oscillating emotional channels between partners, which contributes to emotional stability for both partners”. Even though “oscillating emotional channels” sounds an awful lot like vibrating chakras, I wouldn’t dismiss this concept as woo woo science. Most of us first experience emotional co-regulation as children, receiving and mirroring the reassurances (or the distress – then considered dis-regulation) of a parent. When our caregivers are responsive to our stress, we become attached, trusting, and eventually capable of soothing ourselves and others. Sounds like the equivalent of a lovely exothermic state to me.

That’s when I had an ah-ha moment. I realized my reactions to all things Donald have varied in relation to whom I was dating. In a past partnership, one that was often defensive and contentious, I could get cross eyed with rage whenever a Republican opened his mouth. But in my good relationship, where I experience more positive interactions than negative, I don’t care so much about The Donald. My irritations are tempered by my man’s presence. Around him I feel tranquil, more stable. The first time I snapped at him he diffused my ire by pausing to ask if I could give him the benefit of the doubt. That extinguished my lit fuse in no time.

Don’t despair if your partnership feels as though it sometimes sucks more energy than you believe is sustainable. It’s likely we’ll experience both endothermic and exothermic states within any given relationship, times when you’ll need more co-regulation than you can provide. Like any scientific experiment, you’ve got to plot your data points over time to determine the outcome of your chemical reaction. A dominant state will emerge after which you can draw your conclusions. The question is, how long should you plot this data?

And there’s nothing wrong with remaining within a relationship that might lack long-term stability. There’s something to be said for seeking out the combustible good shag. Hot sex can be the goal. In fact, I’d recommend experiments in the form of flings and casual good fun, as long as you’re honest with your reactant about your chemical intentions. Just be prepared for the volatility that may follow.

Love, Karin

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