I fully agree with you, don’t need anyone else defining my relationship. Neither government nor religion. 38 years ago she first asked me to marry her and I said no, I will never marry. We went back and forth on that issue over the decades, but as we enter old age, it just seemed wise.
In the US where I live, a civil ceremony is a legal marriage, and that’s what we did, right at the courthouse. Previously we were in a domestic partnership, which required no ceremony just signing the papers, and gave us many of the legal rights of marriage. I’m not a Christian, nor a member of any major religion, so I would not avail myself of that type of religious ceremony anyway.