While this might sound very sarcastic in spirit, but it's honestly not. I'd suggest making your own boardgame. Do you have some old plastic armymen lying around? Get those, a dice, a ruler and some random clutter and give it a try. Like... The guy with the sniper rifle can shoot up to three ruler-lengths and rolls a four or lower to hit, et cetera.
It's an interesting thing to try when you've run out of games to play!
Another thing I usually do is to look for interesting old games at garage sales. They're usually cheap and can turn out rather fascinating. If they're incomplete, you can just butcher them for parts or rules to use in your own game.