I was proud to have an amicable $500 divorce. I didn't realize managing the finances of co-parenting would be much harder.

• Sheri Atwood was proud that she managed to divorce amicably for just $500.
• However, navigating co-parenting expenses with her ex eventually led to animosity.
• Atwood invented a system where she could upload receipts for her ex and keep detailed records.

This as-told-to essay is based on a conversation with Sheri Atwood, founder and CEO of SupportPay. It has been edited for length and clarity.

I was five when my parents got divorced, but their separation was so tumultuous that it shaped my whole childhood. The money they spent fighting us could have bought a mansion, but my siblings and I were barely fed and living in a one-bedroom apartment. I lived in 24 different places before I was 18 as they battled for custody.

I was determined not to continue that kind of life. I was the only one of my siblings to go to college. While there, I met a marine in Tijuana and married him at just 19. Our marriage was OK at first, mostly because my job in corporate cyber security meant I traveled constantly.

We had a baby when I was 25, and almost instantly, I realized I wanted a divorce, and my ex was fully on board. Our relationship wasn't healthy, and I didn't want my daughter to grow up with that. I did all the paperwork and paid $500 for the divorce. I felt we had dodged a bullet by having a cheap, amicable divorce despite having significant assets, including multiple homes and a boat. I was proud that we were both focused on what was best for our daughter.

After the divorce, we started fighting about money

After the divorce, I felt like we were constantly discussing — or arguing over — money. He would pay $20 to register our daughter for soccer, and I'd pay $40 for gymnastics, so we were always figuring out who owed whom. I would spend $100 on shoes, and he'd say there was no way shoes cost that much, so I'd have to send him a receipt.

We had the same issue with our shared custody calendar. I'd put my frequent work trips on the calendar, and he would lose the link and ask me to resend it.

I wasted a huge amount of time and energy managing our co-parenting. It was incredibly stressful. Soon, the friendly feelings from my divorce were out the window. My ex and I had a lot of animosity because we had different values around money and challenges communicating about it.

I realized everyone talks about an amicable divorce, but no one talks about what comes after that.

Automating payments allowed me to let go of frustration

When my daughter was seven, she needed emergency brain surgery. That was a wake-up call for me. Until then, I was spending so much time working while nannies took care of her. I realized that if I were going to work that many hours, I wanted to do something more personally meaningful. To me, that meant ensuring my family and others had a better way to manage the mundane tasks of co-parenting, like handling payments and the calendar.

I used my tech background to create a platform to manage payments, schedules, and communication between co-parents. Back then, a text from my ex could distract me from work and disrupt my focus, so I also put communication in the app, which would send me a notification that I could deal with when I was ready.

By the time my daughter was 9, the app was live, and my ex and I began to use it. Having everything in one place allowed me to let go of so much frustration and the time I spent talking to my ex about money. That way, I could focus on what was important: our daughter. My ex even started using it with another ex-partner he also has a child with.

I had let go of my negative feelings, too

Time and time in my life, I've had arguments over money. It's not just with my ex. It also happened with my siblings when we were caring for our mother, and again after she died and we needed to settle her estate.

Having a platform to handle modern family finances takes some of the emotion out of these transactions. Of course, that requires a shift in mindset too. For example, I realized if I wanted to get paid, I had to show my ex receipts for my expenses. He wasn't asking out of spite. He just genuinely didn't realize how much things cost — like those $100 shoes! Being able to upload a receipt kept things cordial and helped me get my money.

Most parents want to support their kids, and they realize kids aren't free. But they don't always understand the costs, and tempers can quickly flare around money. Sharing receipts can be a neutral way to show those costs and avoid emotion.

When you have a child with someone, you're tied to them for life. My daughter is now 22, and my ex and I are still sharing college expenses. I've also had people use the app to split wedding expenses or the cost of taking care of a senior loved one. The last thing anyone wants is to make or receive a phone call asking for money. When you can avoid that, you have more time to focus on what really matters: family.