So, so true.
I agree, and I would add to that: once you have broken up, stop reading your ex's blogs. They may or may not be saying awful and untrue things about you (or at least misrepresenting you from a biased and angry point of view) but you don't need to know that. Respect their privacy. If they are misrepresenting you and you know about it, it will only make you miserable and retaliatory and you will continue that cycle, trying to lobby mutual friends to take your side.
Trust that the people who know you both (even if only online) will be able to see that any terrible posts come from a place of anger and hurt, and will respect you for not turning it into a public slanging match. If they can't see that - if they take your silence as an admission of guilt rather than maturity - then you have lost nothing in losing their good opinion of you.
Do not complain about or criticise your ex to other people: it will make it more difficult to heal the hurts later, when you might be able to rescue a friendship from the ashes. After all, you were attracted to one another once, for more reasons than just physical appearances and you have an intense history of good times as well as bad, so there is a good chance of building a strong friendship in the long term, if you can just avoid reacting in anger in the short term.
And, yes, absolutely: Move on.