Separation agreement signed, prior adultery just discovered

My husband and I separated 6/08 and signed a separation agreement four days later. Since that date I have discovered that prior to our separation he committed adultery. I have a couple pictures and phone records as proof. And at least one eye witness who saw them together.

(As it turns out this same woman wrote up and notarized our separation agreement as well.They are still spending time together to this date. I have proof of that as well. Also have proof he purchased big ticket items for her before we separated.)

In our separation agreement we did divide assets, in which I was extremely generous. I didn’t know about all this before and thought we might get back together after some time apart.

My question is, now that I have proof of his adultery can I use that against him when I file for a divorce and change what was agreed to in our separation agreement?

Also do I have a chance, with the proof I have, to pursue the woman for criminal conversation / alienation of affection? Do I need more proof?

Unfortunately you will not be able to change the agreement. In North Carolina adultery is not a factor in Equitable Distribution.
With respect to the divorce, North Carolina is a no-fault divorce state, which means the only grounds for divorce (aside from the rarely used divorce based on incurable insanity) is a period of separation lasting one year and one day.
You may pursue an action for criminal conversation or alienation of affection based on the proof you have, so long as your separation agreement does not contain a waiver of those claims.
In order to be successful in an action for criminal conversation you must prove that this woman and your husband had intercourse. This means you will need more than photos of the two of them together and phone records.
As for alienation of affection, you simply need to prove that you and your husband had a loving marriage and that this woman’s malicious actions destroyed the affection he had for you.

If I can get him to verbally confess to sleeping with her and record the conversation, would that be proof enough?

Not sure I could get him to confess to it happening before we seperated but he might admit to afterward. However our seperation agreement does say “LIVING SEPARATE: Husband and wife will continue to live separate and apart , each at such place of residence as he or she may freely choose, free from all interference, authority and control, direct or indirect, by the other party, as fully as if each were unmarried.”

Thank you very much for your time and help on this!

Yes, an admission would be admissible in court, make sure to record the conversation for the best results. North Carolina law allows post date of separation conduct to be used to create and inference that the conduct was occurring prior to separation as well.

Thank you for the help.

You are most welcome. I wish you the best!