Sometimes the grieving process cuts deep after a breakup. You may never forget the trauma of losing someone you once had a strong connection with and loved deeply but it gets easier with time and the pain eventually fades.
Things aren't black and white and everyone copes and deals with things differently post breakup. The important thing to do is to eventually come full circle after experiencing the low points, grieving for a time, and eventually start the healing process and work your way back up and pick up the pieces until your whole again.
Doesn't necessarily mean you find someone else to fill the void because filling it can mean something different for everyone and for some simply finding yourself again is enough for them to get going again. In the meantime, if you need to vent or need an outlet for yourself that's perfectly okay. It's not good to bottle things up indefinitely, it's practically impossible to so without hurting yourself in the long run.
It's the sort of thing you don't want to linger for a long time or dwell on, at least from my personal experience.