When two people marry they become one
Really? Do they? How does that work? Do they both give up their individual personalities, never disagree and always want the same things? I don't know anyone like that.
I gave up my last birth name when I married the first time. I always regretted it and when we divorced, I reverted to my fathers last name, the one I'd had from birth. I debated with myself whether to take my mother's birth family name, or my maternal grandmother's last name but decided to stick with the name I'd had most of my life, till that first marriage. I married (bravely I thought) again several years later. We discussed the name thing and agreed I'd stay with my name and he'd keep his. 40 years on, it's still working well. WE never did become one but that doesn't seem to have spoiled anything or made us any less married.