@Boredofmyself I am so sorry that this is your life, and I really hope that sometime in the not too distant future you find the "energy" - for want of a better word - to start making changes to yours and your children's lives.
May I just share a funny little snippet from my Wedding Reception (2nd marriage) - a long time ago now? The Best Man gave his speech, which was almost entirely about my new MiL. He did mention my DH, but only about how and why he became friends with him. That was apparently due to my DH's Mum talking to the Father of my DH's best friend about my DH not having any real friends - so between them, DH's Mother, and best friend's Father, cooked up a smashing little idea, best friend's Dad told best friend that he had to be friends with DH, and hang around with him. This was the first my DH had heard of it, but he didn't seem to be at all embarrassed about it, if it had been about me I would have been mortified that that had happened, and even more so that it had been broadcast to all of our guests.
There was no chance of anything being at all about me though, I don't think it ever crossed my DH's, or the Best Man's mind that I was half of the reason for the Wedding! My husbands speech was quite sweetly I suppose, all (yes all) how great my oldest child was - and yes s/he was brilliant, so that part was fine. The fact that my DH didn't mention me once did upset me a little, but I have never told him that. However, much worse in my eyes was the fact that he didn't mention my other children either, and they were there!
I had agreed with my DDad that he didn't need to do a speech this time (he was older, and not in very good health), so that was the sum of the speeches. I think that if I hadn't been in shock over the previous two speeches, I would have given an impromptu little speech agreeing how wonderful my eldest child was, but also pointing out that the other ones were as well!
Sorry OP that my funny 'little snippet' took so long to tell. I just want to add that all these years later I think my DH married me because everyone else had turned him down, and he wanted a wife and family like everyone else. He spends as much time as possible away from, or ignoring me, but starting up conversations with practically anyone else.
Unfortunately for him, I have my own ill health now, and he is my carer, so he does have to spend more time with me than I am sure he likes - I think that he has tried not to, but he has been making little comments lately that show he finds me a burden. I am a burden (even to me), so I can't blame him for that. I do think he gets quite a bit of pleasure out of his 'friends' and family saying how good he is to be looking after me, but there again, don't we all get pleasure if we are praised for something - well I expect that is so, but my Very Dear Mum died a long time ago now, and she was the only one who ever praised me, but I did feel a warm glow when she did.
Anyway @Boredofmyself I am not suggesting that you should leave your DH, only you know your marriage, and whether you think it is worth trying to save, but please don't be me and suddenly find yourself an OAP, with a lifetime of "funny" stories to look back on. By the way, I am still very much in love with my DH, so I have never seriously thought of leaving him, but I couldn't complain if others knew the truth and told me that I had made my own bed, so I had to lie on it. 💐