See in reality in many cases and probably most, there isn't a wrong and right in relationship failures. Yes there are some cases where there is abuse and/or cheating and such but many many times it's just that the relationship didn't work out, the two people didn't get along, didn't see eye to eye etc.. and in that there's not really any fault to be attached to any one party. Yes we all feel it was the other's fault but in truth, it's probably not anyone's but the fact that it was a personality and value mismatch and that's ok. let them move on and you can too...

Enjoy the new person you meet and date... and keep all your lessons from the past relationship to help you to see the signs of this mismatch if there is one, earlier.