7 hard truths about adulthood that my 20-year-old self would never have understood

While working hard is a must in every area of life, it's hard to imagine or accept that sometimes no matter how hard you try, things won't always work out in the end. That doesn't mean you're not smart, strong, or valuable, just that other people are too, and you can't win them all.

This was a devastating lesson to learn, and one that didn't necessarily sink in after the first or even third failure. However, it instilled me with a humility that has been invaluable.

We all know that money doesn't automatically equal happiness, but you don't understand when you're young just how important it is in life. Without it, life can be a serious struggle, leaving you unable to pay bills and put a roof over your head or food on your table. If you can manage that, having just enough cash to cover the necessities means being unable to buy yourself new clothes or go out for dinner with your friends because you're short on funds. It's demoralizing and even quite scary, but learning this lesson has definitely been a catalyst for being even more ambitious than I was before.

At 20, you think nothing of staying up all night binge-watching TV or not coming home from the bar until the early hours of the morning. After all, you're only young once and you should be out there making the most of it, right? Well, sort of.

You realize once you get older that sleep really is important and that without it, your brain and body can cease to function. Perhaps I've just gotten boring now, but I never sacrifice my beauty rest and I notice just how cranky and unfocused I am without it.

Eating greasy takeout every night, throwing back drink after drink at the bar — many 20-year-olds assume that's just what you do at that age and that you can be health-conscious when you get older.

The problem is, as you get older — even just into your 30s — you realize that you've already done a lot of damage to your body that is hard (and sometimes impossible) to reverse.

For me, my terrible diet and lack of exercise meant I started my fourth decade on this planet pretty overweight, and it's been a serious struggle to reverse the problem. Suddenly, I take all the health conditions that run in my family much more seriously, but I definitely didn't back then.

It's true. When you're in school, making friends is as easy as turning to the person next to you and striking up a conversation. Not so when you're in your 30s, 40s, and beyond. Sure, there are social clubs and even colleagues that can become friends, but I still struggle to make new connections on a daily basis, and it's really disheartening sometimes.

When I was 20, I had a lot of ideas about what life in the next 10 to 15 years would be like, and I'm here to tell you that my life now is nothing like that.

I never thought I'd be a married stepmother living in a foreign country by the time I was 35, nor did I think I'd be able to make writing and editing a full-time job, as much as I would have liked to have imagined such a thing.

The lesson here? There's not much sense in worrying about the future. You just have to work hard, be kind, and hope for the best.