I’ve never been pregnant. Never had a scare, or even a period more than one day late. When I started having sex, I assumed that the specter of an unplanned pregnancy was a rite of passage, like getting wisdom teeth or voting for president.

In my 20s, I thought that I was missing an important maturing experience by reliably avoiding pregnancy. In my 30s, I realized that I didn’t want children. And I felt pretty grown up about the decision, even though others don’t always react that way.

For example, a few years ago, I went out with a man who had children. Derek, who was 44 to my 36, had a son at age 18. We had a rather heated conversation in which he insisted that he was more mature than me because he was a parent and I was not. By his reasoning, he was more of an adult at 19 than I was at 36. Because babies. Hogwash.

My dad also seems to think I’m not an adult. If I tell him that I’m meeting up with some girlfriends, I get a lecture about not putting my drink down and not taking the subway after dark. The same lecture, mind you, that I’ve gotten since high school. Yet knowing that I’m going on a date with — or even with a group containing — a man, all I hear from my dad is a cheery “have fun.” Like I’m in danger alone, but not when a man is within earshot.

My father is on the whole “you don’t have kids, you’re not an adult” thing, too. He definitely thinks that I can do what I want, especially with my money, because I don’t have to spend money on braces and school trips and another mouth to feed. I suppose that rent and utilities aren’t grown-up expenses?

I get that raising children gives you responsibilities and requires a person to make sacrifices and tough choices.

But being child-free, even in my 40s, does not mean that I lack responsibilities and get to do whatever I want. I moved out on my own, got a job and have paid my bills since in my 20s, so I’ve been quite mature for quite some time. Even if I do sometimes get drunk on a Tuesday and fall asleep in my clothes. People with children can do that, too, if they get a babysitter.

And yes, I know that children are expensive and would make a significant dent in my disposable income. But I still have expenses. And because I don’t have a partner, there’s no one to help me make rent or be a safety net if I were to lose my job or be unable to work. There’s no one to fall back on but myself.

In fact, taking care of myself, on my own, is the most grown-up thing that I have ever done. And it’s not easy.

In my 30s, shortly after that date with Derek, I entered the hospital for treatment for bipolar disorder. At the time, I was manic, which, for me, meant partying and sleeping with men I didn’t know and getting very angry at many people for little reason. After I crashed into depression, I couldn’t leave the house for work without crying. I couldn’t make it through the day without getting hysterical in the bathroom.

Finding out that I was bipolar and learning how to treat it changed my life significantly. I had to take medications twice a day to regulate my mood. I had to attend regular therapy to handle my emotions. And I had to consider how my disease would affect every area of my life — from exercise (you can get overheated quickly on one of my meds, so I always need plenty of fluids); to pain relievers (only acetaminophen, no ibuprofen).

Even though it has been years since my bipolar disorder was diagnosed, I still have a litany of responsibilities relating to my disease. I count my pills constantly to make sure I don’t run out. I monitor my mood daily, sometimes hourly, for changes and clues as to what the causes could be. I track my symptoms across the months to look for cycles and signs that my medication might need adjusting. I go to frequent doctor’s appointments and have my blood drawn regularly.

Since that initial diagnosis, I’ve been hospitalized twice. That’s what happens when I work too hard or drink too much or stop paying attention to my well-being.

So, you see, I couldn’t possibly take care of another person. Taking care of myself includes making difficult decisions like that not to have children. There are plenty of people with mental illness who procreate, but I’m not going to be one of them. I figure that the money I spend on medications and doctors and whatever other tools I need to stay healthy are similar to the cash required to care for a child. Instead of worrying about a child and tending to him or her, I expend just about the same amount of energy checking in on myself every day.

If adulthood is having responsibilities that you can’t shirk and money you have to spend, I’m an adult without adding a husband or a baby into the mix. Maybe I’ll consider a husband and an adopted child once my condition stabilizes. Or maybe I’ll continue being both the adult and the child in my life.