I have a unique drinking problem. I won't share a glass of anything with my own wife. Swapping spit during a kiss presents no problem, since I am in love. Yet the champagne switch toast? Gross!
I didn't really understand my phobia until last year, when my sister -- who, unlike me, is not otherwise crazy -- explained that she won't share a glass with her husband, either. When we were toddlers, apparently, our stereotypically overprotective Jewish mother warned us how much sickness and death would result from this act of germ-spreading outlandishness.
And so, here we are, in our 40s and, ahem, not sick at all. (To be fair, Mom was merely a victim of her own dysfunctional upbringing. So I forgive her. However, that doesn't solve the problem.)