I've been banned from my stepson's wedding.....

Your stepson and /or his partner are very rude. There is no reason for anyone to be so rude. I think I don't like them.

I wouldn't lose sleep over it.

If you are glad not to be going, then don't lose any sleep over the disinvite.

It's up to your H what relationship he has with his son after this, but I feel you should make it clear that whilst you will not interfere in their relationship, he is not to expect you and his son to be in the same place again.

H can make arrangements for holidays, celebrations etc on that basis.

As you say nobody these days bothers about how they are addressed on envelopes. So, why did you feel a need to comment on it to the senders? Was this possibly the straw that broke the camels back?

Are you intentionally or unintentionally always making
little remarks about what people do and how they conduct themselves, remarks that place them on their back foot and making them feel a bit uncomfortable.

I had a grandmother like that, one of her little remarks could drain any occasion of joy.

Not judging, just asking, but perhaps it might be worth thinking about.

Are you just feeling a relief over not having to go to the wedding or do you expect never to set eyes on them again? Let your OH sort this one out as to how things go after the wedding is over.For the last straw to be not using a surname on an envelope seems very over the top - wedding nerves maybe, particularly as you have managed to get this far.

My husband's ex does that as well phoenixbfh just puts first names on our Christmas card envelope. I'm just glad both exes still send cards.
Maybe as luluaugust said its just wedding stress. I wouldn't worry too much about it now, let your husband deal with it. Don't shut the door on your stepson though things may blow over.

Are your AC going to their wedding?
Was it a joke about the titles? Does your stepson dislike you having the same surname as his mum - if you do?
Weddings guest lists are incredibly tricky for people these days. Friends are in the throes right now of venue finding and making guest lists.
I don't envy them.
A bit harsh to ban you altogether but can you patch it up so your DH doesn't have to suffer?

Frankly, I wouldn't have said anything about the envelope. That may well have been the last straw.

How was your relationship with them before this happened? I have a feeling there may be more backstory here that we have not heard.

I often just put first names on envelopes ,I didn't think it was a big deal.Its a bit formal to put surnames on for family isn't it?

Thanks, All. It always good to be able to bat these things around to gain a sense of perspective.
I'm not usually making odd comments. In fact, I have walked on eggshells for years and often don't add anything to a conversation as I know that it will be taken out of context. Perhaps I didn't need to mention about the lack of surname but I did and I thought I said it in a way that someone would've taken it as constructive and not a put down. My stepson's mother remarried years ago, long before I met his dad so I don't share a surname with her.
It's always been difficult and my husband's mother talked of "blood family" very early on in our marriage which hurt my kids no end. My stepson even said to my husband, " I'll understand if you choose X over me!" My husband has told him that he is his son but I am his wife and will always come first. I don't even know why he thinks his dad needs to make a choice. It would seem that he has quite low self esteem and when we all lived together as a "family" he made it very clear that he didn't want to be part of it and saved up for his own property so that he could move out. I feel for all the kids. Divorce is tough and they have all been touched by it. Maybe one day he will realise that it was never a competition and we can build some bridges. I do feel that we are dealing with deeper and more complex scars than me marrying his dad but, again, i don't think I'll say that. Thank you for listening when I needed to splurge!

Maybe I'm just old fashioned?? I have never, ever heard of surnames being omitted. Even for family. Ok _ I've learnt something new too.

Well - I would just let OH go to it and arrange a nice peaceful day for yourself.

TBH I would neither have said anything about the absence of surname, nor minded in the slightest.

Look on the bright side - you can have a quiet day and you do not have to tread on eggshells all day

I wouldn't worry about the names either. I did go to my stepsons wedding and sincerely wish I had not - not sure if that helps or not.

So hard successfully blending families. Split loyalties, confused teen emotions dragging into adulthood etc.
Sounds as if you are saying that you were invited to the nuptials but when you criticised the way they chose to address the invitation envelope the invitation to you was withdrawn. Why did you say anything? What did it matter?
You said relationships are strained so why pick holes unnecessarily. Perhaps you did it hoping to be uninvited? Let your DH go happily to his child's wedding and enjoy the celebration. Book yourself a day at a spa or go stay over with an old friend so nobody at the wedding has to worry about you. It is your stepson's special day. You and he are accidental acquaintances.

Phoenixbfh what I can relate to in your post was your feelings of relief and no longer having to tread on eggshells in a social situation. I have given myself permission to opt out of these situations as I’m too old to put up with crap.

My son and daughter had a silly fallout and he 'uninvited' her to his baby's christening. She was desperately sad, though I must say she's no angel. I'm sure my son had good reason to uninvite her. I did not ask what was said. It was hard for me and for her children (10 and 11), though they didn't show it and had a good time at the christening. There's always some drama in my family.
Back to yours Phoenix. I don't think you should have mentioned the way the envelopes were addressed. Gosh, how petty of you. But reading between the lines, I think you are glad you are being "uninvited" .......
Btw the relationship between my son and daughter, is ok now....

Perhaps I didn't need to mention about the lack of surname but I did and I thought I said it in a way that someone would've taken it as constructive and not a put down.
Oh dear, 'constructive criticism'
That is very dodgy ground to tread over something that is so inconsequential.

Can you apologise?

You say you won’t stop your husband going, if you told him not to go to his son’s wedding I assume you mean he wouldn’t go?

Sorry but I think it was rather crass to make any comment about the lack of a surname on the invitation. What on earth was the point? Instead of just welcoming the invitation you found fault with it.

Try looking at this from a different angle how would you feel if you found out someone was saying the things about you you have said about this man's mother? And how would your son feel towards the person calling you such things? You weren't involved in the divorce so you can't possibly know what went on. The criticism of the invitation was the last straw but the ill feeling goes back a long way and you have some responsibility for that. Even if she is the worse person in the world she is your step-son's mother and you shouldn't be so critical. He must be very aware of how you feel.

My husband has told him that he is his son but I am his wife and will always come first

If my dad remarried and said this to me or my sibling I would be quite hurt. Yes your stepson made it into an issue but he has probably been quite affected by the divorce, and wanted reassurance that as your husbands child he was a priority. Being told he was second to his dads new wife was probably quite hurtful.

I would expect your husband to say something along the lines of you and his son being equal, not that you came first.

Oh dear, you seem to have needlessly dug yourself into a hole. Personally, I would apologise maybe not prior to the wedding but after as it may be taken that your only apologising to get your invite back. As for your husband telling him that you will always come first must be quite hurtful even if you do. If you feel relief at not going I really would give it no more thought. Incidentally, lots of people put christian names on envelopes leaving surname off.

I would apologise but after the wedding.

If you have to walk on eggshells around him then it is not surprising that you have said something he found cause to be upset about.

I'd stick to hello, goodbye and yes and no next time you have to be in his company but I would avoid having to be in his company as much as is possible. People looking for fault will always find it.

Send DH off to see him alone after the wedding and relax doing your own thing.

If your husbands ex wife has been diagnosed with autism then does that also possibly apply to other family members including their children? If so then that might explain the generally difficult relationships.
The OP has accepted she would have been better not mentioning the addressing; she doesn't ned endlesslly reminding of her mistake.