How To Let Go???

If one says 'Just go away', perhaps that's when they need you most, but are too afraid to ask you to stay. #TheLoveStories

While the other side might say: I want to go away from you because actually I'm also too afraid to ask you to stay!
It's always hard to understand these three things: WHEN is the time to let things go, WHICH things to let go & HOW to let them go???