So you're saying that there needs to be an amendment for every right that isn't specifically named in the constitution?
Correct. The Constitution originally just gave men the right to vote. There was a successful Constitutional amendment for the right for women to vote, for which a super majority of States agreed. By this standard there should be something specific in the Constitution about abortion if you are insisting on the national right to abortion. If a super majority of the States can't agree on it then it is a subject that is still too controversial for a national blanket law.
Obviously, this topic is too controversial for such an amendment. The Constitution is clear: It is given to the States to decide. The same standard is given to all other "rights".
The argument you are making is that you know that there is an agreed upon procedure in place, but you simply don't care. This is a fault on your part.
I'm not sure why you bring up the EU. If a nation state doesn't want to play under EU rules, they can leave whenever they want. I.e., Brexit.
If a US State doesn't want to play under US Fed rules, they can't leave. Not at least without having to go to war over it. I.e., US Civil War.
Apples & Oranges
Actually the Constitution doesn't mention what happens when a State wants to leave the Constitution at all. Some say the lack of a procedure means that it is impossible to leave, but that has not been fully explored. The Constitution doesn't bring it up at all.
But the Constitution definitely does not say that if a State leaves the Constitution that people must start killing each other. That would clearly be a naked act of aggression, and the North was probably guilty of that when they started killing people for wanting to break away from the Constitution.