My best friend had an affair with my wife, he fathered a daughter who I regarded as my own daughter. 6 years later my now ex wife went of with someone she met thro work and I lost contact with my so called daughter. I would like to get even with my ex best friend and sue him for the cost of bringing his daughter up for 6 years and for the humiliation and pain he caused me. Is this possible?

The mother can petition for child support.

As for you suing him, I doubt if you can find a lawyer to pursue it or a court that will entertain it.

No, you can't sue for support because you are the father of record. Suing for humiliation is a losing cause because it's too hard to prove what he knew about and what the pain would be worth.
Do you have DNA proof that he is her father?
Try to curb your pain for the sake of your daughter.
Feel free to be mad at both your ex and your best friend, but not in a way that will hurt her later on.

No you can not, There is little actual loss, being wrong on who the father is, happens somewhat commonly.