DEAR MISS MANNERS: In my group of friends, it is common that one friend will offer to host a gathering and handle all of the food. All they ask is that people bring what they want to drink. I am not a big drinker, but I do enjoy it at these events, and I am rather picky about what I drink. So, bringing my own bottle of wine — one that I know I like — works well for me. The issue is that other partygoers see me with it and want some. I certainly don’t need to drink a whole bottle of wine by myself, but I’d ideally like at least two glasses over the course of a four- to five-hour event. I usua…