Doesn't it suck when the person who is meant to be your best friend replaces you?

I've been replaced by some chick he literally just met a month ago at his new work. We have been friends since we were 8. I actually got upset when my phone rang and it was her on my friends phone trying to get me to come somewhere and I said no I was tired which wasn't a lie. The last time I hung out with my friend he just talked about her a ton and how close she lives to me. I really didn't care. I still don't care.