My fiance doesn't have a best man. Can we have a wedding without one?
Sure. But you do need someone to sign your marriage certificate as the groom's witness. This could be his dad (who could even be the best man). It could also be his mom, a female friend, an aunt -- anyone. But, is it absolutely necessary to have someone physically standing at his side while he says his vows (someone besides you, of course)? Not at all.
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