What am I supposed to do!!!!

So one of my friends (who I’ll call M so that this makes more sense) has a huge crush on this guy (who I’ll call C). They both like each other and are best friends. They have told each other “I love you” but arnt officially dating. Recently someone new came to our school (L), and she had a crush on C. M was heartbroken and upset because C liked L. So I told her that it’s fine we’re only in high school it wouldn’t have lasted anyways and M agreed and got over C fast. About a week later C came up to M and told her that he loved her not L. Now C and M are officially dating and M’s calling me a bad friend for telling her that we’re only in high school and that it wouldn’t last. I was just trying to make her feel better and I don’t know what I should’ve said. I feel like this is WAY to mush relationship drama for high school and I’m over whelmed. Anyone out there got any tips for me?

This isn’t the first time drama between M and C had happened and usually M comes to me for advice and now she won’t talk to me.