discordant couple
n.— «In the discordant couple phenomenon, one partner is HIV-positive, while the other remains negative, even as they continue to live together as man and wife or simply maintain a long-term relations.» —“Aids Spread Relief” by Big Issue Writer East African Standard (Nairobi, Kenya) July 26, 2004. (source: Double-Tongued Dictionary)
Further reading
For rock climbers, skiers, and other outdoor enthusiasts, the word send has taken on a whole new meaning. You might cheer on a fellow snowboarder with Send it, bro! — and being sendy is a really great thing. Plus: a nostalgic trip to Willa...