Mother in law ruined our wedding

We got married this Saturday. It was a wonderful, small ceremony with only 15 guests - we had to keep it small because of local covid guidelines, and postponed the party until this summer. We invited our few guests for dinner after the ceremony and then for a few drinks in our hotel suite. During those drinks, while everyone was having fun, my now-husband's parents asked him to follow them outside and then started to complain about different issues, starting with how we didn't involve them enough during planning, and ending with how we didn't spend enough time with them during the day. He was sad and hurt and couldn't sleep that night - they completely ruined what should have been (and was, until that point) a very happy day.


Now, he didn't tell me the details, but BECAUSE he didn't I know that they blamed me for everything. I had a good relationship with his parents until my mom died a few years ago. They behaved awfully during the funeral, always pushing to stand in first row with closest family, and his mother said a few things that hurt me very much at that time. She probably meant well, but telling someone "at least she's not suffering anymore" and "you should be glad, she wanted to die at the end" while you're all raw and hurting is just awful and our relationship never recovered after that. During wedding preparations, she kept asking me to involve her with choosing my dress "because my mom isn't here anymore". I very much wanted to tell her that she'll never be able to replace her, but held back for my husband, smiled and pretty much changed the topic. I never showed her my dress before the wedding. They also offered a few times to help us with preparations, but due to the wedding being so small, there really wasn't that much to do, and other people already offered to help with specific things, not just the general "tell us if we can help".Then the next conflict situation arose, about me getting ready this Saturday. I wanted to get ready in peace with only my best friend in attendance, but the mil kept hinting about being there, so I invited her to join me early for a glass of champagne before my makeup artist arrives. She came in all huffy and an hour late, with husband's two aunts who I don't really know that we'll in tow, they sat down, drank the champagne and left... I didn't really pay much attention to them because my makeup was being done, and they felt like I ignored them. Then, during dinner, I sat next to my dad and some friends who speak my dad's language, because he was emotional and I didn't want him to feel lonely since the rest of my family all couldn't come because they have covid (my husband's parents only speak German and my dad doesn't, they communicate sometimes through online translators and stuff, but it's exhausting), so again I was accused of ignoring husband's family. Which I suppose I was doing at this point, because I was so happy and didn't want the confrontation I knew was coming to destroy my good mood. I know I'm not blameless in this whole situation, because I feel a lot of resentment towards his parents that I have never addressed to keep the peace and it sort of festered, but what sort of mother confronts her son on his wedding day about her feeling underappreciated and sad, making him sad in turn? I am so angry at them right now for making him feel hurt and even cry, that I can't even think about confronting them about it. If I did, it would all just flow out and probably destroy that relationship forever. I also wonder how much worse it would have been if we had been able to organise our original party with 120 guests and even less time to babysit the in-laws.I guess, at the end, this post has turned out to be more of a rant than a question, but I really need someone who isn't invested in this situation to help me deal with it and how to move forward, because my husband has a good, loving relationship with his parents and I'm hoping I'll never have to make him choose between me and them. I just don't want him to hurt even more.