I fucking love it! (I just started though, so my viewpoint might change in a few years, haha.) I finally get to be around people who share the same passion and interests as I do. Are there moments where I hate my life? Sure, but stress in life is a given. All I know it that I'd rather be doing this than anything else (housewife, office job, retail, etc.). Here's a book I recommend that helped me conceptualize grad school better before I committed: https://www.amazon.com/Getting-What-You-Came-Students/dp/0374524777
Your research will not likely change or influence the world, lol, so no need to be motivated by that.
Lastly, read this book. It will seriously answer all your questions: https://www.amazon.com/Getting-What-You-Came-Students/dp/0374524777
All prospective grad students should read over the following to understand what they're truly getting into / developing realistic expectations before committing a substantial amount of their life to the Ivory Tower. The first link covers toxicity in academia (YMMV), which is more or less what drove me out of lab work and into IT. I personally chose to remain working in academia because I find it meaningful, but in a role that was more insulated from academic politics (vs generic work politics).