Usually the one that doesnt want to be friends anymore wont recognize his/her part in the failure.
In JG wifes thread about being friends with your ex the above comment was made. In failed relationships it's usually both parties that share the blame.
In the past three years since my divorce I have come to except my part in the break-up of our marriage. I have identified areas that I need to work on to be in a healthy relationship. I have actually grown and become a better person, father, and one day maybe husband.
I'm not "friends" with my ex, but I feel we have a good relationship for my son's sake. I hope that she can do the same in recognizing her part in where things went wrong and become better from it.
There is no growth in blaming.