The world being indifferent to your pain is not helping if you're in acute pain. Step outside your perspective, sure. I guarantee you this will not work if you have real issues like physical pain due to terminal cancer.

You should read "A Man's Search for Meaning" sometime. While not exactly Stoicism many of the ideas are similar/related. How a person views and responds to their situation, has a huge impact on them. No one is saying any of this will remove all of someone's acute pain, but as crazy as it sounds, accepting that suffering can lead maybe the pain not being quite so bad.