So, I will forever have to interact with my spouse and his parents, because we have a son together. We are not legally separated/divorced yet, but I don't foresee any reconciliation. My father-in-law, at least acknowledges me, while my mother-in-law tries her very best to ignore me and remain disdainful. Not surprising - I'm not at all offended. My issue is how to address them. I had been calling them Athai/Mama, and changing it to Aunty/Uncle feels a bit unnatural. I suppose it's the right thing to do, but what do you call your ex-inlaws?
I recommend addressing FiL as Mama and MIL as Mami. She is ignoring you, so why still address her as Athai.
Well, I don't call anyone Mami... it would be stranger to call her that. Maybe I should continue to address her through my son...
First I would say avoid situations of addressing them all together. When a situation comes where you can't avoid then address as "sunny's" paati/thatha . (sunny is just the name I have assumed for your son) When you are referring them to someone say : to you mom you can refer as "Ramesh's" mummy/daddy. Ramesh is again my assumption of your hubby's name.
Why not ask them how they want to be addressed? If your MIL is ignoring you then one less problem for you to worry about how to call her.
My in-laws really adore me, although my own mother hates me. Infact my ex doesnt share a great rapport with his dad as his father remarried (in his 50's) and my ex hates his wife. Somehow all the while he ignored I stayed in touch with them and so they insist I consider them as my own parents. So I just address them as mummy and daddy. They adore their grandson and I spend vacations at their place as well.