Sometimes someone have a really beautiful memory at certain time. And they can't remove it from their memory. It can be an inspiration or venom to them. When they can let go and just take it for themself until their rest of their life and just become a memory without expecting more it can be inspirational and makes good spirit to them. But when someone wants more and thinks that they can meet or experience their memory again which is uncertain it can be emotional toxic to someone. It  might be the best time of our life and we feel our best, but it is just temporary, on the other hand our heart wants it lasting long. Just be thankful for today's blessing and memory that is happened in present time. Like a wind, we can feel it but we can't see it, so does the memory, just enjoy it as our inspiration without experiencing them in the actual world. Because human mind can remember the memory and still feel so glad and inspired even it doesn't exist in the present, just in someone's mind and heart.