Claire
It's starting to get annoying you know, people are catching on to what I really mean when I say it. Might take a bit longer with you, you're using more generic terms, like putting things out of your mind, it's in the past. I'm betting you've claimed that you're "fine" more than once and you're probably meaning it about as much as I usually do.
Look, you and me aren't friends, we both know this. And your sister is one of my closest friends. So with both of those facts I am probably the last person you want to talk to. But if you want my advice-- actually screw it, you're getting my advice whether you want it or not, find someone you do feel able to talk to. Actually deal with what happened. Because right now you're not fine and pretending to be is going to drive you crazy.