I feel lucky that many of my biggest struggles in life came earlier on, from about 7-24. Now that I've hit 31 I feel I've finally got a pretty good handle on my world over here. Losing loved ones is particularly brutal - I sincerely feel for those of you here who've gone through this as well. I suddenly lost my little brother in 2019 and it's beyond soul crushing to bear with a loss like that, but it does get better, I promise.
Having mental issues growing up helped me get comfortable with keeping mental tabs on myself as I got older, so I'm very grateful for that. Learning how my ADHD works has been an absolute tremendous help for me as well, and I suspect with a userbase like GBAtemp there are likely lots of ADHD folks here who can relate to some extent. It's apparently very common for dopamine issues to manifest in very self loathing, depressive and "what's wrong/could be better/why can't I" kind of thinking.
Re-framing that into a more stoic and optimistic approach significantly improved my day-to-day for me - this sort of happened by accident, beginning with me binging ADHD content on Youtube and making very simple changes slowly over time. My executive functioning is terrible, but instead of framing this as something to fix, I look at it as an advantage because my behavior and thinking is now predictable and understood enough to strategize around. This happened slowly, over the course of about 6 years or so, but it really did produce a domino effect for me. I went back to school, snagged my Comp Science degree, got into shape, got a decent job, beautiful girlfriend, bought a condo, and I feel like I'm living on my own terms now for the first time.
I think the biggest single change I made that got the domino effect going was honestly getting into shape. I wanted to do so many things to "improve my life", but the "motivation" wasn't hitting me. Once I started exercising, it really helped kick me into gear to where I could reach my goals. It also reinforces the idea of very small, easy changes over a long period of time really, really, really pay off.
Mental re-framing is very effective, imo, and mindfulness is a good starting point worth looking up if you haven't tried it. And if you're like me, thinking something like "If I could just/Why can't I/I wish I could/ I need to improve" isn't nearly as helpful when you can instead frame it like "This could be great/useful/worth trying/make my days even better".