Oh, gawd. I went through the same thing, kind of. My SIL was so jealous of me that she had to tell me that she was more important to my SKs than I was "just DH's wife not their step-mom" This is after I sent SS a message because he bailed on moving to be with his dad (and we had looked at houses to accommodate him and DH was so hurt). I let him know that. Why SIL had to get involved (I'm guessing BM shared the message with her) I have no clue. Except: jealous, narcissist, control freak. This same SIL buddied up to BM after we got married (DH had stayed with her prior to divorce and she is actually how I met him so we thought she was our friend). I ended up telling her she was a jealous, vicious bully and DH cut her off until she came crawling back and "apologized" kind of. Now she's civil.

Good for your FH!!! That is the way it should be. A father who stands up for his rights. There are no excuses for anything else. Sisters, brothers, etc. butt out!

Here is my take on this divisive dynamic.

This is the social view that dad’s wife is an evil, wicked, greedy woman out only for herself. Those children are very, very nice to me, they say, and the kids are very nice to those people! It never occurs to them that the way the children treat you (dad’s wife), is totally opposite from the way they treat auntie or uncle. They simply cannot believe that these innocent any age children could be nasty, so it must be you, dad’s wife that is the problem. In their way of thinking, YOU are the one who is a jealous, competitive control freak. The kids know they can exploit the general belief that stepmothers are nasty insecure creatures, always scheming to drive a wedge between father and children, and so the kids of any age use that twisted thinking to their favour. And amazingly it works very well for them. You will find in almost every case that BM is still very much in the picture, surreptitiously nursing along this division, while protesting publicly that she does no such thing. (cough) And she is believed!!!

Auntie/uncle see themselves as paragons of virtue and a class A parents who would never treat anybody’s children that way. What auntie doesn’t know is that if she were to become a stepmother, and rightfully asked to be treated with respect in her own home, she too would automatically be judged as competitive, jealous and insecure in the eyes of most people and no matter how hard she tried the kids could carry on treating her horribly and receive nothing but support from the uninformed. It never occurs to auntie that switch would happen to her, she actually thinks it wouldn’t, but it would. They don’t know that their thinking is prejudicial. They truly believe it is you personally and you are sorely lacking in their eyes.

Bottom line they have no business involving themselves in these dramas. They are severely invading you and your husband’s territory in what they consider support for these allegedly poor defenceless children. Interestingly enough they also don’t seem to recognize what a huge betrayal that is to their brother. The insinuation being that dad refuses to look after his own children now because that harridan wife of his is wickedly controlling him and so BIL/SIL have to step in and save the day. He was a really great guy before he met her. How insulting is that?

If auntie/uncle is more important and much nicer to brother’s children than you are, then perhaps the children ought to call them the next time they need money or a place to stay. BIL/SIL’s can’t have it both ways, although they will sure try and feel bloody self righteous in doing so because according to them, you are “different” from them and you are the problem. How would auntie/uncle like it if you and your husband felt the need to step in and protect their children from them? I think they would quickly become enormously intolerant. Not so different after all. They just don’t know it. In reality all their meddling does is worsen the problems.