Hi! I'll be glad to be of help with this issue.
I can imagine how frustrating and confusing this situation must be for you. You are clearly a loving and caring mom. You ex seems to be the type of person that is called today as "feeling entitled". In other words, if he wants something or something he wants seems right and justified to him, then everyone else is obligated to make it happen for him.
And this is actually the key to my answer to you that you need to consider and think about.You are not obligated to make it happen for him. You are a good person who is used to people reciprocating: you're nice, they're nice back. Your ex is not like that: he expects that you should do this because he wants this. So, you are right to take this stand.
It is not the ex spouse's responsibility to bring his children to his wedding. He needs to arrange for trusted adults to do this. It is inappropriate for you to go to your ex husband's wedding. You are not friends. Your connection is strictly through the kids. It is in fact not healthy for you to be involved in his wedding.
The kids are going now old enough that you can explain to them that when they were little kids, you could make up stories. But they are now old enough where if they do not want to do something with their dad, it is between them and their dad. You can help them in terms of telling their dad, but you can't lie or pretend for them. They have to have their own relationship with their father. You know how it sometimes can be yucky, but he is their father. You can help them feel better and handle things better, but you can't lie and pretend for them. Why not, mom? Because as they are now old enough to have opinions and feelings that are their own, the lies and pretends grow and grow and it puts mom in the middle of their relationship with their dad. So, you're doing the right thing and stand firm.
Okay, I wish you the very best!
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