I’m not mad, and I’m not carrying a grudge about the Big Freeze. The most frustrating part of the power grid failure in Texas 3 1/2 months ago is we don’t know who to blame for the suffering and damage. The memory of the Big Freeze in February is fresh in my memory because it’s still costing me money. In April, I turned on my central air conditioning for the first time. It didn’t work. The Big…