DEAR MISS MANNERS: After 22 years together, my “husband” and I are finally getting legally married — a bit tardy, as same-sex marriage was legalized years ago! We’re neither young nor rolling in cash, so we have a very tight budget and need to keep the guest count on the low side. I would like to include two or three of my co-workers with whom I’m close, but I’m concerned about other co-workers feeling slighted. How does one manage this kind of situation? GENTLE READER: A wedding is not (or should not be) a networking event. Therefore, etiquette actively discourages inviting co-workers who ar…