Two ways
1.) Take a break. Gaming can be a very hobby that one becomes very invested in and passionate about. In some cases, it could be the things that keeps your sanity through a difficult time. So it's no surprise that it becomes a default pass time for a lot of people, but what happens when you're default don't work like it used to? It's a weird feeling, having the amazing console or PC you dreamed of as a child, yet you aren't chomping at the bit to play it like you thought you would. If this is happening, do something else. I don't care if that gaming PC costed you $5000 USD, just find another hobby for a while and come back later. You might just need a break.
2.) Integrate your love of gaming into other pursuits. As an adult or even as an older teen, you're more likely to feel guilt because you don't feel productive when gaming, so make it productive. Write articles, make guides to help others, make Youtube videos, create fanart, whatever. Then, playing a video game feels less like a waste of time, and more like developing a skill and creating something, because it's now the first step to doing just that.