Could you maybe explain it to them when it's not occurring?
They have to be made to understand that it's not voluntary and that you're literally unable to form words because you're overwhelmed. They might not get it at first but if you're consistent in how you explain it they might slowly absorb the message.
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The Party told you to reject the evidence of your eyes and ears. It was their final, most essential command.
If you're not careful, the newspapers will have you hating the people who are being oppressed, and loving the people who are doing the oppressing. —Malcolm X
Just a reminder: under international law, an occupying power has no right of self-defense, and those who are occupied have the right and duty to liberate themselves by any means possible.