If oil prices leap while our dollar plummets, we will have to do without cheap oil for heat, car fuel and industry.
We can heat our homes with wood, and the forests of the northeast could use firewood thinnings done, but there will not be enough sustainably producible firewood to replace all the oil burnt each year for home heating. Hence we will need to increase home insulation and lower thermostats, and wear more clothes.
Coal could be used more for heating, too, but only safely with furnace conversions - burning coal can melt wood or oil furnaces and releases carbon monoxide.
Making nitrogen fertilizer for agriculture uses a lot of energy, which growing legumes can substitute for, as legumes, in partnership with microbes, make air's nitrogen usable. Natural gas is used to make most nitrogen fertilizer now, but when oil prices soar, natural gas prices follow.
So expensive oil won't be the end of the world, if we have a plan to deal with it.