Getting back to the OP itself, as other posters have mentioned, there is considerable variety in the types of remedies available for breach of contract, so we shouldn’t start with the assumption that all known remedies for breach of contract should automatically be available in the context of marriage.
For example, if I contract to buy a specific piece of land from you, and you renege on the deal, I can get an order of specific performance from the courts, ordering you to transfer the piece of land.
But specific performance is not available for other types of contracts, notably contracts of employment/personal service: if I hire you to work for me, and you change your mind and don’t show up, I can’t get a court order forcing you to work for me, because personal service can never be compelled. All I could get would be damages.
That rationale would apply with even greater force if someone ever tried to get an order of specific performance for marriage - it’s just not available.
So that’s one point to bear in mind in relation to the OP.
Anothre factor to consider in response to the OP is public policy and legislative changes. It used to be that marriage looked a lot more like other contracts, with remedies that related more to contract law: - if you promised to marry and then broke it off, at common law you could be sued for breach of promise - which was similar to the law governing other types of failure to fulfill a contract, although only damages would be available as a remedy;
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only the “innocent party” could sue for a divorce, based on the other party’s adultery - which looks pretty much like the idea of fundamental breach - only the party injured by the fundamental breach can sue to rescind the contract, not the party who actually committed the fundamental breach;
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only the innocent party was entitled to alimony, not the one who committed adultery/fundamental breach.
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if someone lured away your spouse, you could sue for alienation of affection, or “criminal conversations” - which looked sort of like the tort of interfering with contractual relations.
But in most jurisdictions, these types of actions have been gradually abolished at the same time as no-fault divorce has been introduced. The policy choice made by the legislatures has been that while marriage has some aspects of contract to it, it’s really in a class by itself and that the law governing it is unique to this very personal relationship, not simply a variation on contract law. So instead of applying contract principles, legislatures have crafted legal principles that only apply to marriages - like no-fault divorce, needs-based support laws, and so on.