I don't understand why your H does not think you should. So the exW has not moved on, thats her issue not his. By having you there it does not rub in her face that he has moved on.

I would ask your SS in your H presence if he wants you there, if he says yes then say "Great I would love to be there"

And with split families ( I am Catholic and my SD did this 2 1/2 years ago) you sit in separate rows. One set of parents BM/SF/grandparents in one row, and BF/SM/grandparents in the row behind, or vice versa. Your SS can sit at the end of which ever row he would like. There is a point in the ceremony where they ask that the parents come up with the child. So then just the BM and BF go up with SS. It just takes a minute, no big deal.

Its a great ceremony and a big deal for the children. I went and my H and I sat behind BM and her now H. We don't talk and have not gotten along in a while but we just sat. No need to converse at all.

I've got to be honest. When I was growing up, I could really care less if my SM was at my events or not. I know every relationship is different, so this might not be the case with you and your skids. They might want you there but just don't want to upset BM. The people I wanted there the most were my mom, dad and grandparents. Don't get me wrong- I was always polite to my SM. My parents didn't sit right next to each other, but all of my family always sat in the same row. My SM did come to a lot of my events, and I always politely acknowledged her (and still do). But there were some she didn't come to, and that was A-OK with me. Whenever my SM and mom were both at events for me, my mom would politely acknowledge her. She wasn't friendly to her, but she was civil. I think civility is all that is required on everyone's parts.

As a SM who now gets along well with her SDs, they've invited me to things. BM never shows up at any of their events- she always is getting together with friends or doing things that are, in her mind, more important than being there for her kids If it's something big, like a piano recital, awards ceremony, or something to that effect, I'll go, because they've told me they want me at the major things but if it's something smaller and I can't make it because of other plans or work, I don't go. They understand. My DH, however, always goes. He gets a lot of joy in seeing how his kids have grown in the activities they participate in.

Maybe you and your DH could come up with a compromise. You both go to the skid event, but don't sit next to BM. However, don't sit far away enough from her so that the skid whose event you're going to is looking all over the room filled with people for you. Maybe you could sit a row or two behind her, and let your skid know where you'll be sitting in advance. If BM has her family there, then hopefully she will at least be nice to you in front of them to avoid embarrassing herself in front of her family. Then when the event is over, go give your skid a hug and tell them how great they were and how proud of them you are. If your DH wants to go say hi to BM and her family for the sake of the skids- fine. But by being there, you'll have conveyed an important message to everyone- that I am also a member of this family now and you need to accept it. As far as respect from the skids goes, it also relays the Principlist's message that "you don't have to love me, you don't even have to like me, but you WILL RESPECT me." You're their father's wife- they need to treat you with civility and respect. If you decide to go to these events, your DH should give BM some advance notice, so that way she can have some time to calm herself down and come to terms with it, and he should say you're not trying to replace her in any way as the mom, but remind her that you do a lot for the kids when they're with you and make sure they know they're loved. and hopefully by doing that and conveying that you're not trying to replace her, it will help her to at least make nice to you. He should also add that, "I know the parents of our kids' friends, the kids' friends, their teachers, coaches, and both of our families would be there, and I think it would be in the best interest of everyone there that we get along and be civil. I know it will be a really great event and am really looking forward to seeing the kids in it, and am so beyond proud of them. For the sake of everyone there I think it would be best if we are all adults about it and just focus on how great our kids are doing and what a wonderful event it is."

Or, you might want to give the skids some say in it too. Of course, they shouldn't have the final say, but they can have some input. They might be happy with the way things are. If there's going to be a change in this issue (you start going to events), give them several chances to express their feelings about it, but let them know they're not making the final decision- the adults do that. If, in the end, the final decision is that things stay the way they are, know in your mind that the only reason he's going is for his kids. He has an obligation to them to be there for them. Also, think of it this way: if you don't go, it's one more time you don't have to see the awful BM and that will make things peaceful for you. Maybe a compromise is that DH could quietly exit for a minute and go out in the hall and give you a call. Then after the event is done, he could pull the skids aside for a few minutes, call you again and have them say hi to you. That way, he's killing two birds with one stone- he's being there for them but also acknowledging you. Maybe when he goes, he could sit next to one of BM's parents or his family. That way, he's still sitting in the same row as her and the skids don't have to look all over creation for him, but he's not sitting next to BM.

If in any way you sense that what I said above (about the skids wanting you there too but not wanting to upset BM), have your DH talk about it with them. They might feel a little more comfortable talking to just him about it. He can tell them, "this is your event, your time in the spotlight, and you have the right to have everyone and anyone you want there. If you are uncomfortable about this situation in any way or just want to talk about it, you can always come to me. I love you more than you will ever know, and words can't express how proud I am of you."

Whatever you decide to do, know that you're the bigger person and just continue to be emotionally there for and support your DH and skids. I'm sorry this is so long- I just wanted to present some options and my perspective as both a SD and SM.