<human>: Posted this over on /r/relationships, they said it would be better posted here.

We live in NY.

Last night I found proof that my wife (F/32) of almost 2 years is cheating on me and plans to cheat again.
She doesn't know that I know yet. I'm looking for some good (not necessarily) legal advice on some small steps I can take to tilt the divorce in my favor. We have separate bank accounts, no kids, and we don't own a house (we rent). We have all of our wedding gifts in a joint savings account (~$30k). She's under my health insurance and her cell phone is part of my wireless plan. Rent is split down the middle and we try to keep the expenses fairly equal (although I believe I've paid more into shared expenses that she has, but it's debatable).

I don't necessarily want to use the cheating during the divorce negotiations, but I would like to keep it in my back pocket in case she makes it uglier than it needs to be.

She cheated, but I'm operating under the pretext that we both played our part in the degradation of the marriage (no, I didn't cheat). I want to keep things as quick and fair as possible. I took pictures of the evidence.

Looking for general advice (like don't move out first, itemize the shared expenses that I paid for (phone, car/health insurance, groceries, etc...))

Can you condense the text into a few key points?
<bot>: Wife doesn't know that I know she cheated.. How can I set myself up so that I have the upper hand in the divorce before she even knows that we are getting divorced?