Cheer up, spring is almost here and our mood seems to have a way of turning around as well.
You've been dealt a lot of bad stuff lately. It's no wonder that you're questioning yourself. There is nothing wrong with you that a little time and space from the ex won't cure.
First things first. You need to deal with the grief over your friends murder. I'm sure that this is a big part of your mood. I told you that I went through the samething when a friend was murdered, and you have to reconcile yourself to the facts and accept it. It's hard at times and it may sound cold but life goes on and you have to move on with it.
As far as ex goes, you've had some pretty big doses of her lately as well. Wouldn't you say that this is the biggest amount of time that you've spent in the same room with her in quite a while? No wonder everything is so close to the surface. You've been subjected to the marriage according to ex and you've had to listen to all of the things that YOU did to cause the end of your marriage all over again. You had put this all behind you, don't let her takeaway your peace. All, you know that none of that is true. Distance from your ex had shown you that what really was. Don't get sucked back in and PLEASE don't re-hash everything in your head. Your ex has major problems but you didn't cause them.