Outcomes and incomes

Today I knew that I would be a little unsteady emotionally, and what I mean by that, is that today would have been the day, last week that my dearest friend was dying. The whole week has been challenging. From his family descending on me and all wanting answers and re-assurance that they were good to him, to my ex-husband deciding to throw me the cold shoulder when I chose supporting the family of my friend over some pre-scheduled thing with him.
In fact that brings me here tonight. I had a long and unexpectedly frank talk with his mother. My friends death has made me see some things that have gone on, a bit differently now. I suspect that his death marks a true turning point in my life.
I have finally given up my attempts to make right my post marriage status with my ex-husband. The way he behaved when I chose my friends' funeral over his issue was just the last straw,and I have had many last straws I have felt,but this time,I think that that one did the trick.
I have come to terms with the fact that he is just a selfish,thoughtless person.I have hoped that he could mature and get past certain behaviour that he now shows me, but this will just not be the case. In fact,I do not know what convinced me that I could have a civil or any relationship with him for that matter?
The way of most people seems to be the best idea....to go our separate ways and not speak, maybe ever again, apart from discussing our child.
I know that what I am writing sounds a bit harsh,but I can see no alternative.I really have had enough. I have tried and tried,and tried. When my friend was alive, he used to say, god knows you've tried. Now I ask myself, why? To what avail have I even bothered? Every time I reached out, I gave ten miles for a fraction of a centimetre in response.
This is just not worth it. I throw down my hands,I give up. I can do no more.I do not see the point.