It was fun while it lasted sentence
Said when one is looking back on something enjoyable or worthwhile in the moment that it was happening even though it was impermanent
I know we have to part ways this weekend, but remember all the good memories we've made. It was fun while it lasted.
The party came to an end, but it was fun while it lasted.
To imply the one with a good memory
To make someone recall something.
To make someone remember something
If you say something slips your memory/mind, you mean that it is forgotten.