Returning Soul Parts that you are holding: 

In the language of the soul, the way you "get things done" is by making clear what your intent is.  The job is accomplished by doing something as simple as - going outside, getting a twig, and snapping it in half to indicate that you would like to release the souls you are holding.  You can take an object such as a quartz stone that represents the person's soul and give it to the person as a gift.  Speak a request that your guardian spirits return the soul pieces you are holding.  These and many other techniques work.  It is only necessary for you to send clear a message that you wish to release the soul pieces, so whatever method that seems appropriate for you will work. 

In some cases it is difficult to let go when someone is no longer in our life, such as a lover we have broken up with.  You may need to first do the work of being willing to release what you are holding of them.  Perhaps you are unwilling to let go of the control.  Don't judge yourself but instead try to get to the bottom of why you are holding on.  Remember that this part of their soul is needed for them to live their life fully, and that it makes your life more difficult when you try to hold on.