What Can I Do About Sexual Harassment At A Small Company?

I work for a small family-owned business.

One of the married employers is having an affair with another owner. There are pictures going around of him standing in his doorway (which is directly across the hall from her office) masturbating and then going into her office, where she continued the act for him. This all took place within thirty feet of his wife's office, which could have been seen by anyone walking out of their office into the hallway.

The company was recently sued for sexual harassment by another employee for sexual acts from this same man, which was settled out of court in the ex-employee's favor.

The daily strain of coming to the office is getting hard to handle. I can't afford to quit, but health-wise I don't know if I can continue. I have had a headache for four solid months due to the strain of this situation. I am three years away from retirement, which makes it difficult to quit, and I also carry the health insurance for my husband and myself.

Do you have any advice for me?