Weddingbee boards

There is indeed a protocol for this (which varies slightly depending on who is hosting: I'm going to assume it is you and your husband - to - be). It also varies depending on whether you are following the English/American protocol or the Continental protocol, but for weddings the Continental protocol is more normal because it seats the newlyweds together. It also gets a bit non-standard because you have a preponderance of female guests of honour and an odd number. But here it goes:

The host and hostess sit in the middle of one long side of the table with the hostess on the right.

The male and female guests of honour --at a wedding that's the best man and the matron of honour-- sit to the right of the hostess and the left of the host respectively.

The next-most-honoured lady and the next-most-honoured man sit opposite the host and hostess respectively.

The rest of the guests get sorted into order of precedence and are seated outward toward the ends of the table, generally following male-female alternation where possible, with the most-honoured people sitting closest to the hosts, with the hosts' side of the table being considered slightly more of an honour than the other side, and in general avoiding sitting spouses, siblings, or parents and grown children next to each other.

That bit about NOT sitting spouses next to each other will come as a surprise to anyone who doesn't move in consular or "society" circles unless they are over, oh I don't know, mayber 45. It used to be common knowledge that this was correct form, but somewhere along the line most people went informal for all non-wedding events and also lost the skill of making conversation to casual acquaintances. So vary that rule for anyone who came of age after the eighties or so unless they are socially sophisticated.

Normally, natural parents take precedence over foster parents or step parents, but that is something you have to decide for yourself -- you can seat your aunt in the place normally reserved for the "Mother of the Bride" if you want to send the signal that that is how you think of her.

At the Bride's end of the table, the groom's family take precedence over hers. At the Groom's end of the table, the bride's family take precedence over his. Closer relatives take precedence over distant relatives. Earlier generations and elder people take precedence over later generations and younger people. People in positions of responsibility (judges, doctors, teachers, elected representatives) take precedence over people who do not hold such positions.

Applying these rules and assuming that your guests are all socially sophisticated, you would then end up with:

Best man's daughter  ...

Groom's stepfather    ...    Best Man's wife

Matron of Honour      ...     Groom's stepmother

Groom                     ...     Bride's Mother (or Aunt)

Bride                       ...     Groom's Father

Best Man                 ...     Bride's Aunt (or Mother)

Groom's Mother        ...     Matron of Honour's Husband

If your guests are going to be uncomfortable sitting up to eight feet away from their spouse for over an hour, and you therefore want to sit spouses together for a result (which is a bad idea, but it's hard to convince modern girls of that) you end up with:

                                             ...   Groom's stepfather

Matron of Honour's Husband    ...   Groom's Mother

Matron of Honour                    ...     Bride's Aunt (or Mother)

Groom                                   ...     Bride's Mother (or Aunt)

Bride                                     ...     Groom's Father

Best Man                               ...     Groom's stepmother

Best Man's wife                      ...     Best man's daughter