@Outra Hi! Good on you for joining this forum and having an open honest discussion about your thoughts. I never had the thought process of no treatment or surgery - all I wanted was to be rid of it!
There are heaps of resources within this site as well as Counselling as this is a decision. although it is yours to make, shouldn't be taken lightly with you having regrets later. Counsellors will give you good coping mechanisms as well as us here. There's always someone on the forum at all hours that will come on and comment. No judgment!
Please take some time to research before cutting yourself off from opportunity of medically being rid of cancer. It is a huge decision and I wish you wellness. Take care