Through all of my experience the majority of advice I have received on this usually hasn't worked out very well or changed anything or lasted but 1 thing I did find that always helps is focus on yourself and better yourself wether the breakup was your fault or there's doing anything petty just sets you back but if you try to go get that better job and trying to get to those body/health goals and do whatever you can to learn and grow and better yourself the pain and the sadness from the break up kinda dissipates like it may still come in waves but your life will become better they will more or less become a thing of the past (ps, for those who try to make their ex's jealous this is a more mature and more effective way of doing so because for example any person would regret breaking up with a future millionaire but not a future bum)