Possible age discrimination by employer, employee's rights under WA state employment law

I was let go after a week and a half after being hired. My new boss said he had made a mistake and that I didn't fit the culture of the organization after all. He said I did not relate well to the clients (board members and donors) of the organization, but would not give specifics.

I told him this had never happened to me in my entire career, and that I had literally turned down one job offer and put off pursuit of another job so I could work for his organization because it was such a perfect fit for my interests and abilities.

He made his decision after a week and a half that included intensive travel together, a full weekend away, and after-hours work. Shortly before letting me go,he asked, "Do you think you have the drive and stamina for this job?" I told him I thought I did, and was giving it my best.

This appears to be age discrimination since I wasn't awake and energetic at any hour he needed me in a high functioning condition. Despite being 61 yrs old, I am in good physical condition (work out regularly). However, I need a reasonable amount of rest each night and time to be functional in the morning after a strong cup of coffee.

The only other specific he gave after letting me go was that it was a "cultural difference," suggesting that I wasn't sufficiently high class to mingle with his associates.

What bothers me most is that he never stated the deficit in my work while I was working for him, so I never had an opportunity to correct whatever it was that he thought was deficient. I have good social skills and a long and successful career in fund development at respected institutions and organizations in Seattle, including the Univ. of Washington and the Hutch. And I am always wiling to modify my behavior, dress, hair style, or whatever, if my employer lets me know I need to change.

Before starting the job, I signed a work agreement acknowledging that the position is "at will." However, the hiring letter also said: "…You should expect to be told when you are performing below expectations and given an opportunity to remedy your situation. If you continue to perform below expectations, you should expect to be dismissed. While you are employed at will and can be let go at any time, it should be a rare occasion that you are not given an opportunity to remedy your situation.”

Another person who met him said, "This man knows no boundaries" when it comes to the way he treats employees.

Frankly, this situation has caused me not only mental suffering, but may have damaged my career. A news article and photo had already been published in the newspaper; friends had been notified; people keep asking how I like my new job. I have to tell them I was let go, but I don't exactly know why.

So, does it appear that he violated any federal labor laws, or should I just accept that he's a jerk and go with the flow?