it is NOT an ACTIVE process. It is a totally PASSIVE process.
You do not let go as in move on and get over her. You let go as in letting go of a child on a bike, knowing that they are going to crash one day, but you still have to let them go.
You let them go, and live your life and work on yourself, for the day they come back...
You be there for her, when she wants you, not you be there for her when you want to.
...you hold to something THIS tight, you break it. You hold onto someone this tight...you smother them.