More and more, the relationship between Greece and the rest of the euro zone is like a marriage that, to everyone but the two people in it, seems doomed. Voters in many other euro countries have little stomach for further helping debt-ridden Greece avoid the consequences of its past overspending. Meanwhile, Greek voters are rebelling against austerity but have not coalesced around any realistic alternative. There’s still hope of a reconciliation, but bringing it about would require each side to adjust its outlook in ways that, recent history suggests, are entirely out of character.