first of all, here is a big *hug* for you... you are obviously hurting and in need of support, thanks for reaching out. Even if this might not be a poly thread I certainly don't mind the opportunity to care for someone.
It seems to me that the guy should be the first to go. It seems that his presence in your life is not helping you feel better about yourself and is in fact adding to your issues.
Losing your friend is the root of it you say. Good for you realizing that. That is a big start.
When I lost a dear friend who committed suicide a few years back I decided to have my own personal ceremony for them. I did a ritual around their passing. I lite candles, meditated on them and our friendship, went over in my head why they did such a thing and left me behind and came out of it realizing that I was happy for them and that they were now where they should be. I could move on.
I'm sure your friend would want to see you are happy. They wouldn't want you to self destruct as you are now..... perhaps there are other friends of theirs that would join you if you want? Perhaps there is a place you used to go.... I don't know, only you do. Make this your own thing and really go to town on it.
Then sit and think and write, whatever you like to do, about where you will go next in order to find a suitable future for yourself.
I'm not always a big therapy fan, having been one.... I see it's use and see how it works for some, but haven't always had success with it myself. I get more success from really doing the work to go inside myself and bouncing off my friends and family what I have found... maybe that is what you need to be doing. Just because it's just you in this world doesn't mean you can't be your own best friend. That is where really happiness begins anyways.
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