Email Evidence of Adultery?

What is the name of your state? Taxachusetts

Hello,

I've been collecting an archive of my wife's email correspondences with her lover for some time. Several messages mention them sleeping together on seperate occasions. I'm curious though if this type of evidence would be accepted in court? I mean, I obviously didn't ask her for a copy of these.
Would a judge simply say "Bah, those could be fake", or could they be allowed with some other evidence? I'm looking for experiences with this type of proof.

I know I could just file for a no-fault divorce in my state. However, my wife is a Russian national and her residence depends upon our marriage. I think proving she had an affair would improve the chances that she is deported.

Not that I'm bitter

maybe I can help with this,..
Even though Chatting and email is not considered adultery, I think if you had the emails stating the fact of her cheating, you could use this as evidence, I am sort of going through the same thing with "a friend" and I know eventually it will probably end up like your situation, if I were you I would contact a lawyer and see if you could use it as evidence.
hope it works out for you