Yikes! Need help, please.

[TrentC]

Even if you find stuff he will deny deny deny so be sure you want to open up that can can of worms. If you confront, they will run even further.

But ultimately, there can't be any reconciliation of the marriage until or unless the other person is out of the picture.

If you find proof, hold onto it until you need to use it.

If you don't find proof but are sure something is going on anyway, all you can really do is work on yourself and hope that the changes are enough to bring them back around. And be prepared for the "I've been seeing someone else" bomb...