Marriage is defined as the legal union of one man and one woman. That’s what a marriage is. Every adult not already married has the right to marry. As a matter of law every adult male has the right to marry the woman of his choice and every adult female has the right to marry the man of her choice. So no adult is denied the right to marry.
Many adults choose to not marry; they choose to “play the field,” or they lack the temperament for marriage, or they never met the “right” person, or they simply don’t like the other gender. People choose to marry for all sorts of reasons; love is only one of those reasons. One of every five male homosexuals will marry the woman of his choice; one of every three lesbians will marry the man of her choice; these unions often produce children. So every American has always had an equal right to partake of the social institution defined as a marriage – the union of one man and one woman.
Homosexuals have never been denied the right to marry; they have simply chosen to not marry; they are now clamoring for the invention of a new social institution and they want everyone else to pretend that this new institution is also a marriage just like the traditional institution everyone else calls marriage. Their neediness is endearing, but every same-sex union will always be one genuine sex organ short of being the union of two complements which is the defining feature of a marriage – it is the marrying of two complements that is the essence of this institution. Any other arrangement is just a marriage parody.