Sandra D. Bricker. Nashville: B&H Books, 2013. 297 pp. (Hardback). It just wouldn’t be Christmas without those sappy, romantic, barely believable TV movies. Well, how about a sappy, romantic, barely believable book? “Merry Humbug Christmas” is the story — or stories — of two friends who spent the last several Christmases attempting to avoid the festivities. This year, things are…