First Mothers day NC with MIL

Respect her NC and maintain your relationship with FIL, send him a FD card from you. Up to DH to send him one of he wants to.

Don't bother you are just setting yourself up for a fall again leave things be x

Stop giving her and her family headspace.

Doing anything for her for Mother’s Day was never your job to begin with. Leave it to your husband to make a decision.

Leave FIL up to him on Father’s Day as well - your only responsibility is to facilitate Father’s Day on behalf of your own children when they are little.

With the sad loss of your own mother, I totally understand why you would want to develop that relationship for the benefit of your children. But she is never going to be an adequate grandmother, nor any kind of motherly figure in your life.

Stop trying to pacify and appease. Doesn’t matter what she expects. Let her reap what she has sown.

Only if she's very rich.

You can only control your own behaviour, not anyone else's. If you don't change your behaviour then nothing will change.

It's really easy to just not contact someone who has no intention of contacting you. You literally do nothing,

You are giving this person too much head space. No one cares about it except you and you've been given a wonderful opportunity to easily break away, so take it.

Dont forget; MIL went NC with you. She has made her position clear. She doesnt want contact with you.

If you do anything, you are again overriding her boundary to be NC. This isnt about what you want. She made her position clear. Until SHE changes that position; its not your situation to progress.

You work on you.

we were always taught to do our best to be decent human beings and do the right thing

No, you were taught to override you (and others) boundaries and enable bad behavior in the name of keeping the peace, swallowing your own discomfort so that it avoided conflict.

People pleasing/fawning.
Fawning is a behavioral response to fear or threat, often described as a "people-pleasing" or submissive coping mechanism used to avoid conflict and ensure safety. It involves excessive flattery, over-apologizing, and sacrificing personal needs to appease others. It is a trauma response designed to make oneself agreeable to a threat.

Key Characteristics and Behaviors of Fawning:
Constant People-Pleasing: An inability to say "no," often agreeing with others to avoid conflict, even at the cost of one’s own values.
Excessive Appeasement: Going to great lengths to make others comfortable or happy to manage their emotions and reactions.
Submissive Behavior: Displaying overly subservient, flattering, or helpful behavior to de-escalate tension or potential danger.
Loss of Self: Ignoring one’s own feelings, thoughts, and needs in favor of adopting the preferences of others.
Over-apologizing: Frequently apologizing, even when not at fault, to prevent criticism or conflict.

Whilst I don’t disagree that OP shouldn’t send a card in this instance, this feels like a weird take? Mother’s Day is to celebrate the maternal figures in your life and therefore I would argue grandMOTHER is included in that

Don't reward her behaviour. Detach. Teach your children that when someone treats you badly it's ok to not want them in your life. Celebrate yourself as a mother to your children. Plan something nice to do. It's your day, you should enjoy it and get on with the rest of your life without drama.

Op, you know she won't change, nor will your SILs. Stay out of it, send her nothing and be happy and in peace.

This. Keep it simple. People who are good to you, treat them the same. People who are bad to you, treat them as if they don’t exist.

Not your circus, not your monkeys.

If you DH feels like sending one he could do so. You'd be a mug to send her a card after all that nonsense. Model how you'd like your children to behave - have a sense of self-worth and don't pander to people who scream at you and insult you.

@UncannyFanny I used to send cards for Grandmas when DC were little. Card shops sell many such cards, it's not unusual for some families to send them. My family were all about celebrating mothers in the family, my DM has always sent me a card since having DC

Do you know why she treated you like she did? Because of the very reason you are asking about sending her a card. She treated you so badly, ignores your kids and here you are wanting to run after her? That is exactly why. Stop being a mug and have some respect for yourself. No one will respect you if you don’t treat yourself with respect

How does your husband feel?

Just don’t. But do Father’s Day as usual.

How do you want people to vote, and on what basis?

It’s clear from the current outcome of the poll that it’s … unclear.

Don't.

Not only is it sending mixed signals; you also open yourself up to more abuse. It will not go the way you wish (rose tinted spectacle).

Stay away. She is an adult and makes the decision every day to not reach out to you or your children. You cannot change her behaviour; you only control how you react to her actions. You cannot make her see, you cannot understand it for her. She isnt stupid, she is a grown adult making life decisions. Let her.

You cant fix what you didnt cause. Trying to do so is fruitless and it is fawning; teach your children that their actions have consequences, and you cant control the actions of another adult.