Should i expose the affair, or?

[Jefe]

If i say nothing, won't she just continue with impunity? If i say something to family/friends, i'm sure she'll be pissed and upset, and it might backfire even more.

She's going to continue whether you give her "permission" or not. You out it, and it's almost guaranteed to backfire. But Starsky is the bigger expert on that. In my opinion, outing it makes you look bad in the long run and makes the pathway back home very difficult. It pits your family and friends against her and it will be hard to turn off when she comes home. They can often carry resentments for many years (sometimes forever) against a former wayward spouse. The scarlet letter approach is far too dangerous for those reasons.

What is one to do? It tears me up to know now its still continuing, but do i turn the other cheek and just try, as hard as it might be, to walk the path of not talking to others about my daily reality?

Find a few (very few) people you can trust to keep quiet and support you.

After weeks of feeling like some slight movement "might" be possible in a positive direction, the finding out again, and her admission she wants to leave is causing me to lose focus all over again. I fear by not taking charge and outing it to shine a light on it, then i take on the hurt and pain all myself, and just have to suffer through it.

You're going to take on the pain and suffer through it anyway. You out it and you're going to suffer more, promise. Based on what I am reading here you're not "taking charge" by outing it, your trying to make sure she feels the same level of pain you feel. You need to take a different approach. First, if you are truly committed to standing and saving your marriage, realize that there is a ton of pain that is going to go along with it. There is zero way around the pain only through it.