ignore them completely like they don't exist. Then pay more attention to the 2 or 3 that were right there the entire time. I find losing friends is a blessing unless it's because of false rumor or something. Hell I rarely have more than 2 oer 3 close friends I'll tell anything to since it's just a pain in the ass having a lot of them and it takes a lot of effort where a couple of friends you can put the effort of 3 into one and show them you're a real friends like if they have to move I don't wait to be asked and just show up saying I heard you were moving today, they will love you for that.