Assuming it's just a game burn out your facing and not an life depression here's a few techniques that might help you find the fun in gaming again:-Go Retro:
Visit good old games (gog.com) or Humble Bundle and look around for some old favorites you enjoyed many years ago, chances are it'll be priced $10 or less and playing through an old beloved game (Ice Wind Dale, Fallout, Master of Orion II ) can help remind you why you enjoyed gaming back in the day.Go Co-op:
Grab a game that's meant for co-op play, like Borderlands 1 or 2, 7 Days to Die, or Dead Island and group up with a friend or two. Sometimes gaming solo can get a bit repetitive, and adding in the social aspect of a few friends, the challenge of team work and a new game to experience together can make it fun all over again. (I would recommend avoiding any MMO's however given the grindy/repetitive nature of them can make turn more tedium than fun quickly.)Mods:
Look up mods for some of your favorite PC games, they can add dozens (at least) of hours to the replay and increase the fun factor and challenge of games that have gotten stale.Try a different genre of game:
Been playing a lot of Rpg's lately? (Like Divinity Original Sin: http://store.steampowered.com/app/230230/
) Mix it up with a RTS like Grey Goo: ( http://store.steampowered.com/app/290790/
) Or a FPS like Far Cry 4: http://store.steampowered.com/app/298110/
or Borderlands the Pre Sequel: (http://store.steampowered.com/app/261640/
) or maybe try a survival horror like Dying Light http://store.steampowered.com/app/239140/
or even something more laid back rogue like such as Dungeon of the Endless? (http://store.steampowered.com/app/249050/
Depending on your usual type of game, playing something new and different can provide a new type of challenge and engage the fun aspect of video games your current selection lacks.
Also try not to get too caught up in free to play and mobile games for a while, given they often pressure you into logging in every day for "free bonuses" leading to a feeling of missing out on stuff and changing the game from fun to an obligation/chore which quickly kills the incentive to play it.
If all else fails, just take a break from gaming for a few months, and find more active hobby like skeet shooting, or joining a local IDPA competition group, or even take up model building or home beer brewing for a time, something as far removed from electronic venues of entertainment as possible, then come back to gaming in the fall and see if it's still as fun as you remember it.