I see, thank you for clarifying the situation, Andrea.
This does sound suspiciously like discrimination based on sexual orientation since the employer learned of your sexual orientation shortly before being terminated in a manner which is usually not used to terminate employees.
However, neither state nor federal law currently protects against this form of discrimination unfortunately. Many states and cities do prohibit discrimination in the workplace based on sexual orientation, but in MO only the cities of St. Louis, Kansas City and Columbia protect against such discrimination. I'm very sorry, this is obviously extremely unfair and the laws are progressing toward prohibiting such discrimination, but you would not be covered while working in Arnold, MO.
If you had an employment contract and the employer breached it, or they violated their own policies, that could provide grounds to allege actual or implied breach of contract. If that is not the situation, then the employment at will doctrine would typically govern this situation and you would have no recourse, although I would apply for unemployment benefits under these circumstances.
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