Ok OP I've read the whole thread and you really need to take a long deep breath and calm down.
Please try to remember that for a marriage to work you need to be on the same page.
Yes he's been an utter ass here but you really need to figure out together what took you to this place and where you go from here. Resolution won't be found while you're both in a heightened state of conflict.
The holiday is happening. That's now agreed. Stop sulking and spoiling it for him. It's his first time away with friends in 12 years. He's going to have a ball. Let him go with love.
Plan midterm so you enjoy it while he's away. You have money, friends and family so this is very possible.
Then work on fixing your marriage. It's not good now. YOU shouldn't be so jealous of friends. HE shouldn't be so obsessed with his friends. This sounds like a contradiction but it isn't. It sounds like he is your whole world. You need to remember that you are your own person, find stuff you like to do, start enjoying yourself again and bring the happiness back.
You should be having one evening to yourself every week, no questions asked. It doesn't matter if you're out for dinner with friends, at yoga, gone to a movie or secretly hiding in your bedroom with a good book. It's your time.
From his pov he's been having a great time; work is better, lovely wife and family at home, booming social life. And while I think he has the balance way off he's not totally wrong to be pursuing happiness. You need to prioritise your happiness and then you can both work it out together.
For now tell him you will miss him when he's away but you're not going to argue about it anymore. Tell him you look forward to seeing him that weekend but you really need him to show that it's as important to him as his time away with friends so you won't be booking or paying for anything.