Pain is part of life. If we avoid pain, we avoid living; we only survive. The problem is not the pain, but the judgments and layers we carry around it.
What if there was no cause to our pain? What if we came on earth with a specific pain? Every time we focus on the assumed context of our pain, (that relationship, that illness, the world), the context becomes the thing to change; and we are not healing our pain.
The first step is to really own our pain: this particular pain is mine; it belongs to me. Instead of understanding the reasons, focus on the essence of your pain. The roots are not outside of you but within you.
If you really care for yourself, not because you are special, but because you want to be of service in a way that also serves you, then care for your pain, be responsible for it; and you will feel free.