I think you might want to examine your assumption that there are people who "sail through life." It may seem that way from the outside, and you may even observe people handling everyday stressors well. But I promise you, everyone is struggling. Everyone suffers. (btw, that's actually the first Noble Truth of Buddhism).

But you can learn ways to separate the stress you can't control from the stress you can control (your reaction/behavior), which is the foundation of CBT & ACT (and is the third Noble Truth).

I personally don't think upbringing has a big impact on our natural ability to do this; I think it's mostly genetic. But it doesn't really matter.

The good news is, the brain is plastic, and you absolutely can change your mind and behaviors pretty radically over time. This is the science behind psychological flexibility / ACT—and yes, it does replicate.

When I find myself thinking "some people just have it easier," I try to ask myself "is that a workable worldview? If I follow that train of thought, is that moving me in the right direction? Or is it causing me to give up or give in to resentment and frustration? Could I just let it pass?" You don't have to argue with the thought; you can just notice it and let it float on by.

Years ago I heard someone, possibly on NPR's Fresh Air, talking about how thoughts were a lot like food: just as we can make decisions about what we eat - "no, I am not going to eat that (now|today|ever)" - we can also learn to identify thoughts that have negative effects on us and when they happen we can choose not to think them.

At the time, this sounded a bit fanciful and just a bit ridiculous to me. Over the decades since, it has come to be one of my foundational philosophies. Obviously, I am unable to stick to it all the time, just as I sometimes eat food that I know is going to make me feel bad. But it's there as a guiding principle, all the time.