I'm not in quite the same boat, but I can give you some insight based on my current situation.

I broke up with my ex of 6 years right before leaving the country for 2. I came home on Christmases and did my best to stay in contact, but all it lead to was anguish for me.

Long story short, the group of friends (save for one) had moved on without me. I stayed because I was told we would remain friends (not hearing that just from my ex, but from the others) and the one who is still my friend who is also in that group really wanted me to stay in contact with them. I spent 2 years after getting back in my home country trying to be friends with them only for them to set up separate chats, have get togethers without telling me and having major life events without letting me experience it with them. There was a real two-faced aspect to it; I was being told everything was fine while their actions plainly revealed the opposite. Just this past Sunday, I put my foot down with my friend, told them I was no longer going to put the effort in so I can heal and blocked the other 5 people.

I'm very disappointed in them. How much they hurt me when they were supposed to be my lifelong friends I have now known for over a decade. What I will say is I was not the only one burned. There were 10 people in the group when I got back two years ago, now there's 6. Three others were deliberately excluded before I left (though admittedly they did participate in my exclusion, but I don't begrudge them because they were burned too).

Now, the group consists of two couples (my ex with their new partner and an engaged couple), my dearest friend who is feeling excluded now and a guy who is back in his hometown several hours' travel away for the pandemic who rents a room with the engaged couple. I predict the latter two will leave within a year or two as well based on how things have progressed so far.

Those two couples will likely get more friends in the mix after we're all gone. I wonder if they'll ever accept responsibility for what they did to those who have left, and what they are doing to my friend and the other guy.

The lesson I've learned is even people who are ostensibly the closest to you might take the easy option out and ignore you. To keep stringing you along because it's easier than confronting their own failures to deal with the situation. They may even think they're in the right; protecting your feelings by not cutting you off. Either way, in the end, you may get burned.

Watch out for yourself. Others may not do it for you even if they should.