IC, IC, IC, you need to keep going. You need to walk through all of your pain (some of it/lots of it wont even be A related.
You already know this, you stated it in your last post. If you walk away from her and this marriage you will be packing up this pain and hurt and bringing it with you.It will color the rest of your life.
Don't let it.
You may as well dig your heels in and start healing right now. The trauma of her A feels like the extra weight you can't carry, but really VD, ALL the weight you have is too much. Peel it off in layers with your IC. Take one hurt at a time, go through it, understand it and feel the hurt of the little boy and work your way through every trauma and instance of hurt. It's the only way you will get to the other side.
Pull the threads apart and examine them. Don't run, don't hide. You will hate yourself for giving up.
I had a ton of FOO issues, abuse, trauma, pain that I stored in pretty little boxes until I sat myself in IC. I could take out a box and show you what was inside, I was able to list everything that happened to me that made me who I was...but I kept my little boxes with all of the hurt and pain tucked neatly inside.
I didn't get that I had to unpack them, that boxes only clutter my heart my head and my ability to feel things authentically.
So I went to IC and started to unpack. One box at a time. Pain from years back I didn't even allow myself to see came out. I began to find me, know me and appreciate me. One by one I threw the boxes away. It wasn't easy. I had a few boxes I fought to keep, but over time I let them go.
Over time you will to. You don't have to know how to do this. There isn't an answer that I can give you except time and lots of feeling/working through the hurt.
Your wife is doing her part. She isn't perfect and remember, it's only been a year...this shit isn't quick. She is walking in the right direction to get/be healthy.
You need to do the same...one step at a time. It's frightening and you don't know how you will feel about the M or the future direction you need to go in until you get to that fork in the road.
Give yourself a break, feel the anger and continue to communicate with your wife. Let her know your needs. She is doing the work and eventually what's "right" will become second nature to her. She will think about her actions, even the little ones, and how they affect you/the family and herself. It's a process.
Give yourself permission to not have all the answers but allow yourself the time to find them.