It’s going to take more than a one-week rally to rehabilitate shares of companies in the oil patch. A week after rebounding oil prices pushed energy shares to their biggest rally since October, renewed selling in crude has the group poised for its biggest monthly decline since May 2012. Only one company — Columbia Pipeline Group — in the 40-member gauge has posted a gain this month, with eight tumbling more than 20 percent. Even after a 4.6 percent surge last week, the group’s 10 percent December rout will cap its worst year since 2008. Crude has plunged 12 percent in the month, poised for its biggest two-year slide ever amid waning demand from China and Europe, while fresh data signaled a spike in American stockpiles. Selling in energy shares — the most beaten-down group in the Standard & Poor’s 500 Index for two straight years — may also […]