Ancient Philosophers resembling the "stoic" community made use of the technique known as "contemplation of your own death" to live a worthy life. They used to cultivate the habit of thinking that they are dead already and the day they are living today is the bonus they received from god.
But here is the thing, these impacts are positive as well as negative. It totally depends upon the degree of it's execution and your perspective. That's why sometimes they are beneficial other times they may backfire!
I have realised that when the time's destined, people will come into your life & when the time's over, people leave. The person who loves you today may not love you 3 months from now, because the time's over. Everything will come, stay and leave when it's time. Everything comes, stays and leaves to teach us something, to make us grow.
It is man's duty to live in conformity with the divine will, and this means, firstly, bringing his life into line with 'nature's laws', and secondly, resigning himself completely and uncomplainingly to whatever fate may send him. Only by living thus, and not setting too high a value on things which can at any moment be taken away from him, can he discover that true, unshakeable peace and contentment to which ambition, luxury and above all avarice are among the greatest obstacles. - Seneca
If yes, good. This will instantly sky rocket the set point of your spirit + emotional health + happiness. Generally speaking, it will Optimze your good emotions right away.
We like to miss the way someone made us feel rather than the way he or she acted and treated us. We remember the way people affected us and not the people themselves.
When we miss someone, we don't miss the actual person but the feelings that person gave us in past. We miss the way we felt and the people we became when we were with him or her.