Barron YoungSmith in Slate http://www.slate.com/id/2202431/ points out long distance relationships hurt the environment, speaking of one couple in particular who see each other once a month:
"Indeed, for her, breaking up would be about 10 times better for the environment than going vegetarian."
"The Local Food movement encourages us to cut CO2 emissions by calculating food milesthe distance a meal travels from production to the dinner tableand eating only what's produced within a 100-mile radius. Isn't it time for a Date Local movement, too?"
In the old days when I was a commuter student at UMSL, dates who lived across town were "G.U." -- geographically undesirable. I haven't heard that term much since, but it may be coming back into fashion.