Hi DG, quitting and rudeness are an unfortunate part of this otherwise great game, but you don't have to put up with it on a regular basis.
There is the abovementioned country club for example. But if you look for a variety of challenges with players of all levels and creed, whom rarely quit, then the WGTLS is the site for you to explore.
WGTLS is a site where you get into free competitions, such as ladders and guilds and meet some really good people from around te world, whilst playing golf on the WGT site.
Just google for World Golf Tour Ladders System, or WGTLS, and have a look.
Regards