Don't share this with anyone, but I'm going to cheat on my wife.
Why would you want to jeopardize your marriage?
I feel that I'm no longer interested in my wife and I cannot be faithful to her
Marriages are hard work but cheating on your spouse won't make it better. It is not good to cheat. Your marriage will have a harder time and will probably end.
Who will cares if my marriage ends? It's not as if there are laws having sex outside marriage.
True, but it's still dishonest. I recommend you both look into couples counseling. If you can't see a future  for your relationship, rather than lead on your wife, you should begin divorce proceedings.