This breakup was a while ago. It's not recent.
Most Helpful Guy
You can't 'make' yourself 'want' anything. Let time and nature do its work. It's perfectly OK to not want to move on, to hold on to the memories as long as you can.
Spend all the time you want looking at pictures and mementos of your time together. At some point, you'll package it all away with a sigh and not look at it all again for years, and then you'll probably just smile to yourself and toss out all but maybe a couple things.
For now, enjoy being sad. It's part of life at every stage. Life brings us together, and, sooner or later, separates us again. Even after decades, you'll have to separate by death no matter how badly you want to stay with someone.
So don't fight your feelings..sadness will always be mixed with happiness.