What Happens Next -- Once You've Discovered Infidelity?

Once I discovered his infidelity, I spent countless months chasing after the fact that I wanted to catch them together so I could actually "prove" that I knew he was cheating. That did not happen, and I guess it was because I told him about my suspicions and he got better and better at hiding things with her. He became a true master of arts at hiding and being sneaky. I ran myself ragged over trying to follow him or looking through his van for clues of other women that would have been sitting on the passenger side seat. I wasted so much of my precious time and I wished now that I would have been able to let things go and move on, but I wasn't. What happens when you discover the cheating? Do you wait for more proof, or do you get it all right out there right away?