programmatically set win forms user controls to nothing on dispose

I have vb.net winforms application. It has memory leaks which is caused by a third party control. I am left with the option of reducing instead of eliminating the memory leaks.

The form has several user controls declared as Friend WithEvents. They are not GCed when the form is closed, because the form is in memory and it holds a reference to the user control. However, when I set the user control references to nothing on dispose, the memory leak is reduced.

Now I want to expand this to the whole application instead of just one form. How would I use reflection to scan through all the user controls and set them to nothing on dispose ? Interesting to note is that the user controls are declared using "Friend WithEvents" signature. Is it possible to somehow use this while scanning ?