Unfortunately there will always be those breakups that remain as such, and really, many of those really are best that way when we take a long-term view of the situation.
Time really is a great healer — ish. That is, as more and more time passes by, more and more life has been experienced. And that often tends to help rub away the marks left by the relationship.
Sadly, we humans are excellent at living in the past. And so we can carry forward those feelings from the past — mainly those which remain unresolved — into the present time, helping to keep them fresh. Not great.
It's important to realise this.
How much you do this, and how deep the issues affect you will determine how well the "time is a great healer" thing pans out.
If your relationship was not salvageable, if you've given it your best shot and think it is time to move on? Then you probably would like help to do just that. To move on.
I think this coping with a breakup article is a good place to start. It covers quite a bit of ground.
If you’d something more comprehensive, though, then I have a new moving on course that will be more effective.
I may write more on this in the future, though the above resources are well worth your effort to investigate in the mean time.
I wish you every success.