And I'm not back peddling here, but I was playing devil's advocate to some degree. There was a lot of judgment regarding your W and saying she abandoned the kids, so that makes her wrong and you right.
In all fairness, from where I sit, it looks like she abandoned the kids. But I do not know her reasons for leaving without the kids nor do I know why she has not contacted them or visited them as little as she has.
It sounds like you are doing the "right" thing for the kids and it does not sound like you would deny your W access to the kids. Other than that, it would be up to her to maintain her contact and connection with the kids.
In the same way that it has been up to me to maintain contact and visits with my kids. And to fight for what is best for them within the context that both my W and I can participate and provide for the needs of the kids.
The best that things can be, given the current sitch...