People worked for thousands of years to build up society so that the average person's life is easier and easier. Microwaves, sedentary jobs, air conditioning, and similar modern conveniences have made it so that life is safer and easier to manage than ever before. While this is mostly a good thing, it does create one huge issue: people's lives get easier, and they become more fragile and sensitive. This is discussed at length by researchers such as Johnathan Haidt who point out that a life lived without anyone challenging your ideas or without facing adversity leads to children growing up unable to handle the stresses of reality when they have to become independent and deal with the struggles of daily life.
It's such a strange time to live because on one hand, life is easier than it has ever been before—from developed countries being able to access all the information in the world and any product or service they could want at the tap of a screen to children in developing countries being saved from fatal diseases in seconds with a vaccine injection. On the other hand, people's tolerance for discomfort has gone down, causing people to be more miserable in many ways than they were before (as demonstrated by rates of anxiety and depression increasing over time). It seems like the easier things get, the happier everyone would be...but that's not the case. So...what's going on?
Well, it has to do with what makes life meaningful vs. what makes you happy. Happiness has two definitions in this context: pleasure and fulfillment. The pleasure form of happiness is the state of feeling good. The fulfillment form of happiness is the state of feeling that you have done well with your life. The irony is that modern improvements have increased the former at the expense of the latter without realizing it.
The cause of this issue is hedonic adaptation: your life improves, and then you get used to it and return to your typical happiness "set point" that has a heavy genetic influence. So if you get a promotion, you quickly adapt to the increased salary and it no longer gives you additional feelings of happiness. So you have to find the next thing that makes you happy to keep up. So all of life's modern conveniences are about finding things in life that make you feel bad or experience stress and alleviating the issues.
The problem is, once those are gone, the next generation will not have experienced that issue and won't appreciate the solution as much as the previous one, thus compounding the issue that a person's expectations reduce the positive feelings that they feel and enhance the negative feelings when something goes wrong (because they're not used to it). So now you have two generations: a generation that got pleasure and fulfillment from solving the problem (losing the pleasure faster than the fulfillment over time), and then a generation that derives no fulfillment from the solution but instead expect it and are upset when those expectations aren't met.
Now for the coup de grâce: the new generation has been raised with modern conveniences and access to millions of pleasure-inducing stimuli (e.g., video games, YouTube videos, Netflix shows, fatty/salty/sugary foods, alcohol, pornography, social media), leading to the belief that life should be easy and everything should just be provided to them. After all, if everyone is trying to make life easier, then shouldn't that mean that you should avoid anything hard your whole life?
And that's causing the problem with a lot of people's mental well-being today: life being hard can actually be a good thing. One of my favorite quotes from A League of Their Own comes from Tom Hanks's Jimmy Dugan character when he says, "It's supposed to be hard. If it wasn't hard, everyone would do it. The hard...is what makes it great." That encapsulates how the focus on the pleasure form of happiness sucked away the fulfillment form of happiness. People focus on getting the next dopamine hit and stopped striving to achieve difficult goals that would make them feel good about themselves and their lives. So, like how an alcoholic would cycle between stress->alcohol->buzz->hangover->life->stress->alcohol, more people are cycling between their daily lives and dopamine hits to numb them of any pain or difficulty they face instead of facing their problems head on.
So if you are in that situation, your life will improve immediately if you realize that you are avoiding any challenges in life and numbing your pain with pleasurable activities or substances. But in addition to that issue that you might face, your life can then be improved further by identifying the "hard" you wish to choose to pursue. In A League of Their Own, it was about playing the game of baseball and Dottie Hinson being the best player she could be. In your life, it would be about choosing the challenges that you wish to subject yourself to for your own growth and development. It's why people pursue rock climbing as a hobby, learn a new skill or trade, or build a business. These things are very challenging, and they seem completely counterintuitive if you grew up under the assumption that you should be making your life as easy and painless as possible at all times. "Why would someone do that to themselves?" is what someone might ask if they think life is about parties, travel, concerts, and easy, boring jobs to pay for them. But it's the fact that you pursue growth, which requires you to try something that you may fail at first until you develop the skill to succeed, that will lead you to fulfillment.
When you look around, you'll begin to see it everywhere. Raising children (especially on a tight budget) is hard. Winning the Super Bowl is hard. Building a business is hard. Running a marathon is hard. Getting vaccines to a region without paved roads it hard. Growing crops for your family and community is hard. Working a 16-hour double shift in a hospital is hard. Free climbing El Capitan is hard. So why do people doing these things? Because it's what leads to fulfillment and not just pleasure. The hard is what makes it great. Growth in the form of the pursuit of a goal, the nurturing of others, or the work for money, resources, or skill development is what leads to that sense of meaning and purpose.
The beauty of modern life is because the basic maintenance has become so easy in many ways—all you have to do is perform a repetitive task, pay your bills, eat, drink, eliminate waste, clean yourself, and sleep—the "hard" in life becomes something you more often get to choose. For thousands of years, the "hard" was thrust upon people, whether it was forcing them to participate in wars, frequently giving them untreatable health issues, or making it required to work incessantly just to stay alive. Compared to then, the idea of working 8-hour days 5 days per week, getting shots, and having food delivered to your door is a dream. Yes, there are still plenty of instances of the "hard" happening to you and not from your choosing, but you have much more freedom to choose than ever before.
And that is something that you should do. The "idle hands are the devil's playthings" saying is famous for that reason: if you don't act with purpose in life, you spend time on things that can make your life worse, such as using drugs, having unprotected sex, doom-scrolling through social media, or just worrying about your life instead of living it. This is why there are more single people who are unfulfilled today—they focused on themselves, and they missed out on that cliché "when my child was born, my whole life changed; it was no longer about me" moment that parents have that flips the switch from living a hedonistic life to living one with a definite purpose outside of yourself.
Now, it's important to note that meaning can come from any form of growth—you don't have to reproduce to find meaning, nor do you have to work a specific job or get married or whatever else you might think society is pressuring you to do. Yes, it is true that children, a rewarding profession, and marriage can lead to a sense of meaning, but so can mastering a skill or being a teacher. You really do get to choose your hard.
Just make sure that you choose wisely. While you can always change direction in life, some of the hard things are hard because they require commitment. You generally, for example, shouldn't abandon your children, divorce your spouse on a whim, or quit your job without enough money to sustain yourself and your family. So make sure that you can commit or responsibly transition in another direction (i.e., without hurting anyone) if you do make a choice that leads to long-term responsibility.
Life can be simplified greatly down to the basics. You don't have to do anything above the bare minimum to sustain yourself and live peacefully in society. There are some people who choose to live on the road or the street for the sole purpose of being as free and living as simple as a life as possible. So anything you are doing that's more difficult than that is, in fact, a choice. And with that knowledge in mind, the best way to view what to do with your life from there is to choose your hard. Jerry Seinfeld called it, "finding the misery you can live with" to explain this concept. If you can find what aspects of your life you want to be difficult because it will make it more rewarding, then that's what you should go after.
In short, don't think that the goal in life is simply to live an easy, pleasurable life. While that goal is valuable in many parts of life so you can focus on the most important aspects, the most important aspects are going to likely be ones that are difficult if you want them to be meaningful. While you shouldn't make something like a relationship intentionally harder than it has to be—that's sabotage, not rewarding difficulty—you can always add more difficult challenges to your life to push yourself to be better and accomplish more, which will lead to continued fulfillment as you succeed and thrive through your life's obstacles. Make the right choices for you, and you'll be on the path to life satisfaction.