Have you every heard of a case where kids (mine 11 - 21) don't want their mother back
Sure, and it's usually kids around those age ranges. They are old enough to see the changes in their mom, and to understand how a third party is often involved. They see who left and broke apart their family. They don't like, nor approve, of this version of their mother. They will always have a child-parent love, but that doesn't mean they want to be around her during this time.
The youngest one may feel more of an emotional need for his mom, which is only natural. They all may have to deal with anger in their own way........just as you have to do. It's difficult for adults to find a way to channel anger, so imagine how it must be for kids.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!