You're describing a case of retaliation for resisting sexual harassment. That's illegal for any employer, no matter how small the business. You have the right to file a complaint with the Illinois Department of Human Rights. You should talk to a lawyer experienced with IDHR issues immediately. They'll talk to you for free and will take your case on a contingency basis if they think it's sufficiently supported by evidence.
Resisting this sort of behavior is the right thing to do. This guy sounds like a real creep.
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This creep is retaliating against you for refusing his sexual advances. This is illegal sexual harassment. Your next step should be to consult with an employment discrimination lawyer in your home town.