I always thought that disagreements about money in marriages were about big issues like buying a house, saving for retirement, or deciding whether to take a vacation. Never in my wildest dreams would I have imagined arguing with my husband about Wi-Fi.

The Sunday afternoon sun was streaming through the windshield as I drove home from the grocery store. I wondered how Thomas and I had gotten here.

When we first met, I was impressed by his financial responsibility. He meticulously tracked his spending, paid off his credit cards every month, and had a healthy savings account. This seemed like a good sign. He was a responsible adult who wouldn’t drag me into debt.

Our first year of marriage had been smooth sailing. We opened separate accounts alongside a joint account for household expenses. It made sense at the time. We both contributed equally to the account for the mortgage, utilities, and groceries.

As I pulled into our driveway, I sighed. What had started as practical financial management had turned into something entirely different.

I brought the groceries inside. As I put them away in the kitchen, I remembered how different things were now.

Thomas’s “fair” version slowly morphed into an obsession with sharing every penny. Separate accounts were fine, but then came the meticulous division of every expense based on who used what.

“Andrea, you used hot water for 40 minutes today during your bath. That’s definitely going to run up our gas bill,” he said last month, calculator in hand.

“Thomas, it only lasted 15 minutes, and that’s because I pulled a muscle in yoga,” I replied.

He just shrugged. “Still, it’s extra, so I’m increasing your share of the bill this month.”

I placed a carton of almond milk in the fridge, remembering that grocery shopping had become the next battleground. If Thomas didn’t eat something, it was on me. The yogurt I’d bought for breakfast? Just for me. The almond milk for my coffee? Mine too.

“I don’t drink almond milk,” he said flatly, examining one of our grocery receipts. “That’s $4.29 you owe on the joint account.”

“But you drink the regular milk we share,” I pointed out.

“Yes, because we both use it,” he answered slowly as if explaining to a child.