I can’t believe you went through giving birth, bringing up your kids all alone and supporting your home all by yourself! I’d love to ask how you possibly managed it all, as its really upsetting to hear but that is too personal of course. but wow - I admire you. really!
What made your husband come back to you finally? he saw his 2nd child for the 1st time after a year?! you have a big heart for letting him come back into your life after everything you were put through? how does he treat you now? does he keep in touch with his mum, fam’ etc?
if your MIL says you are dead for her and refuses to see her grandkids – then that is really malevolent and sad. and i have heard grandparents love their grandkids more than their own children!! some people are so bitter and keeping grudges is like fuel to their souls.
you are so much better off without them! enjoy your life and concentrate on bringing up your kids. i hope you have a beautiful future with your family.