I understand that feeling of departing or wanting to depart. It creeps in and can at times be scary or a sobering awakening to the preciousness of life and its changeableness.
I also think that sense of departing is that we are leaving behind all the old ideas of who we are and we are something we never imagined. And tomorrow something else.
I do practice mindfulness or trying to be more alive to this moment. It can be a simple as following my breath and the listening to the birds singing in the morning. Yoga helps me tune in and relax and quiet my mind.
It is surprising that the scattered thoughts can be every where but they do diminish, some days more than others, and then with a few minutes of turning within, quiet reigns for a little bit and whatever gift you have inside can pour out.
One night this came out of the blue

The moon is shining in my window tonight,
Silently whispering in my ears.
Secrets I can never tell
In words... or... thoughts... or deeds.