Our pain and suffering does not come from letting go, it comes from holding on. When we let go in faith and trust there is no pain or strain. It is only when we resist what we know we must do that we suffer. If you are experiencing pain then you are holding on to something that you know that you need to let go.
Fear is holding you back and it is only a creation of the mind, a misguided false sense of protection. Let it go and you will see that all will be well. You know this is true because you have experienced it before. You have let go of your fear in the past and you became stronger, more powerful and more connected to your True-Self, so let go my friend, just trust and let go.