I then proceeded to explode and scream every expletive I could think of at her for doing this and telling her I wanted a divorce.

Bad idea.

You jut gave her the upper hand by revealing your intentions.

Here's what you should have done or do ASAP.

Go to every good lawyer in your are and have a consultation. This way the bitch won't be able to use them because of conflict of interest.

So, the next day we talked and my wife asks me to go to marriage counseling in an attempt to save our marriage.

Don't even bother. You'll be lectured how this is all your fault because penis. Either forgive her, accept your cuck status and move on, or divorce.

Since then I have come to believe marriage counselors are pretty much worthless.

No shit.

Our counselor is a woman and I feel she takes my wife's side in every counseling session we have with her. She tells me my wife's infidelity while wrong isn't that big of a deal and could make our marriage better.

Just as I said. Run the fuck away.

I'm not going to tell wife I am filing for divorce until I move out and serve her with divorce papers.

Smartest thing you've said.

Am I wrong for not telling her I'm planning on divorcing her after all this time?

No and don't let anyone here convince you otherwise.

You are in the right. She broke an emotional contract/bond. You owe her NOTHING!

Unfortunately the law will take her side. Prepare to fork up a considerable amount of money.