A LOT of ridiculous to process here. And for the record, the only reason to have kids is if you really want them.

Now:

Your ex, how could he have fathered a child when he clearly had no balls?

He really needed to man up and tell his mom to STFU.

Your ex-MIL..... The very definition of Makin It All About Me.... sheesh, what a horse's rear.

And finally, I am a big believer in "that which we allow, we encourage."

I think you needed to be your own best friend (since your ex was AWOL) and just tell ex MIL to shut up.

I know that sounds harsh.