Completely agree with Kaffe Diem on reading DR and focusing on yourself. Also, google "affair fog" if you want to understand how your wife likely can't think rationally right now...and it is nearly impossible to actively work on the M together while she is in an affair (EA or PA)
My H has been in an affair for 6 months (I've known for almost 4)...it's a nightmare. I'd advise also reading books on affairs such as Shirley Glass's "Not Just Friends". It really helps understand the motivations behind the affair and through these books...I'd gotten to a place of understanding why my H was doing this.
However, I'm now unwilling to live with my H's affair and I've told him we need to separate. I'm to the point where I'm fairly detached and I just know I deserve better. But, I'm glad I took a few months to try and I believe my H may eventually realize what he's done.
I'd just brace yourself for a long ride. I would really focus on being the best person you can be and on supporting her through this.
M 44, H 46 D11, D9, D5 Married 12 years PA confirmed 9/2011 I filed 3/2012 H moved out 7/2012