Focus on yourself for a few months: fix your finances, get fit, find a project that absorbs your attention. Your brain will selectively remember only the good parts of the relationship, so don't trust that version of your ex.
Chapters
Number one breakup advice is be selfish. Be selfish for a couple of months. Get your money up, get your physique up, get your health up. That's going to get your confidence up tremendously. And find a project to take you off your mind, off your ex. If you're male, female, whatever, just find something to stop you sitting around constantly thinking of your previous relationship. And it's funny, when we go through a breakup, it's called selective memory. We have a way of thinking of all the positive parts of the relationship, and you don't remember all the fights the arguments and the stress.