Sorry to read this. It makes me so mad when I read this stuff! They make this mess and then they not only expect us to accept all of the responsibilities but do it with a smile on our face and a grateful attitude for the crumbs they give us. I see all of these Dad's who still realize that they are pretty much 2nd in line until their kids are raised and I wonder how can our ex's ever reason with themselves that it's ok to shirk their responsibilities? Monetarily I can't complain. Ex tells himself that this makes him a GREAT DAD, but that's all my kids get. Not exactly leaving them with warm fuzzy feelings.
About guy friend, I think that you have listened to your gut and your really smart for doing so. Better to cut it off now while you can still get out of it gracefully. Just remember, these issues will with the kids will probably present themselves in any relationship. We are Moms first and foremost.........
I think you're going to be just fine. You are 1 smart cookie!