Losing three straight sets to Whitney was not what the Bear River boys volleyball team had in mind going into Thursday’s match. But last year’s Capital League champs and Sac-Joaquin Section Division II runners up had other plans and sent the Bruins home with a straight-set loss, remaining a perfect 5-0 in league in the process. Bear River lost 25-18, 25-16, 25-17 on their home court, “It’s a mental thing,” said Bruins head coach Lance Mansuetti. “We lost to (Whitney) at the Placer tournament earlier in two close sets. We need to show the passion and the desire. With the …