Lost_light.................Wow! Talk about being between a rock and a hard place. I think you should confront her with what you found, in a kind way. Don't bring out the big guns just yet.
Obviously there is something going on,( or not going on) in your marriage,or with your wife, that needs to be addressed. TALK to your wife, and maybe get some expert advice, together.
Wingcommander, it sounds like you have been hurt awfully bad, by a woman, and if you have, I'm terribly sorry. Nobody deserves to be hurt by a cheating spouse.However, I don't think Lost_light needs to assume his marriage is over, and find himself a lawyer just yet. I think they definitely need to sit down, and talk rationally, and calmly, about what she is doing.
Good luck, and all the best to you, Lost_light. Hugs.