Perhaps Hadley Freeman’s concept of marriage is too romantic (Weekend, 4 March): matrimony isn’t about frou-frou frocks – it’s essentially about entering into a contract. For religious people, this is involves a sacramental vow, but in civil society it’s about signing on the dotted line, as you do when buying a house or even hiring a car. Civil partnerships for homosexual couples were not just “a sop”: they were about inheritance law and pensions. It is not irrational for Charles Keidan and Rebecca Steinfeld to seek to extend such contract law to heterosexual couples, even if it is hardly a compelling case of injustice. It is more irrational, as Hadley Freeman implies, to suggest that cohabiting couples should have the same rights as married couples. It would be nullifying the case for contract. It would also be removing the freedom of some cohabiters not to be contracted into a legal union.

Mary Kenny

Deal, Kent

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