At this stage, where there is active/willful EA, I think MC probably won't do much for you guys. Just my amateur opinion. But it's amazing that she is still willing to do MC with you! That says something.
She'd probably benefit from doing some IC, if willing, so she can sort out what the hell she wants out of life, marriage and a partner.
Does she work outside the home?
Me: 50, MLC/WW 45 Young kids Nov 2015: BD1 Apr 2016: BD2 Jan 2017: W filed Feb 2017: D final