TLDR: I try to remember why I got into gaming in the first place. To me, gaming is a means to an end. Challenge? Hang out with friends? Nostalgia? Where would I want it to take me?
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Whenever I get in a rut, I go back to the nostalgia associated with classic console games (yes, I'm old). For gaming, not many things put a smile on my face like some Super Metroid or Link to the Past. Many titles are available as downloadable ROMs (stay legal, though: only stuff that you have previously owned). I have also watched a few NES and SNES speed runs on YouTube that brought back memories. Advantages: you get the "nostalgia" quick fix (YouTubers beating games in an hour or so), and it supercharges the memories associated with them. Who can forget the finale of Crocomire? I was a kid back then, and it freaked me out! hehe Point is, sometimes I gotta go back to the basics and remember why I got into gaming in the first place.
Another reason I found that games were boring is that I played them on easier settings. Dragon Age taught me the value of savoring a challenging experience. In fact, it wasn't until I started playing on Master until I truly started enjoying Skyrim into the hundreds of hours. Save scumming at first, but then I started learning HOW to play instead of just standing in one spot whacking away their health. I even sought out combat mods for Skyrim to make combat that much more interesting. I got a little carried away with combining combat mods with Sands of Time (great mod, BTW), but I eventually found a good balance, and found something that kept the game fresh and interesting. Many games can have very sophisticated (or let's be honest, "cheating") AI, but only if you open the floodgates with the difficulty slider. Whatever the case, it wakes me up, and engages me to actually think about what I'm doing.
Finally, online play with friends is the last major motivator for me to keep playing a game. Especially grindy games like many MMO's. If I'm playing by myself then eventually I figure, "what's the point?" However if I'm playing with friends, then the comedy and antics are what keep me going. The same goes for my IRL gaming group. Most of the time we just goof off and bounce jokes off each other for a few hours twice a month; we have an absolute blast--does't matter that our characters are wading waist-deep through kobold blood while trying to outrun a (plot specific) blind Tarrasque! (Surfs up, dudes!) But hey, "WE" made it a blast! Even Minecraft with my son is fun: together.
Failing that, I hear woodworking is pretty fun :) OH! hey, there are these little 3D metal model thingies that offer a good distraction for a couple of hours. Search Amazon for "Metal Earth". Lots of neat little models to build.
Seriously, that's why I'm a gamer: nostalgia, challenge, and community. If I didn't value any of these, anymore, them maybe it's time to move on to something else. What is the underlying reason YOU game? Remember, gaming is just a means to an end. Where do you want it to take you?