> EU treaties are not a constitution and the constitution the people gives itself stands above all
Germany [1] and Hungary [2] played with this fire. In summary, no.
Treaties have force of law. If a country improperly ratified their EU treaties, they need to amend their constitution (if it exists) or admit they never properly joined the EU in the first place. Given the latter means economic collapse for most EU members, it’s not a hard choice.
Once the people choose to no longer follow the EU Supreme Court, thus, as a follow up, no longer choose to follow the EU treaties, they exit the EU just as the UK did.
No country is or can be forced to be a EU member.
Just because there are economic implications does not mean the EU treaties are above the countries‘ constitutions the people actually chose to enact.
This is true of any law, there isn't actually anything except common agreement that constitutions should be treated more seriously giving them extra status, and there isn't anything but the consent of (enough) people giving laws any power: nobody is ever forced to follow any law, they are simply punished if they don't.
However, once you decide to stay within the law it is indeed possible to have EU treaties stand above the constitution. In situations where you've added bits in your constitution that the EU treaty has priority, acting like this isn't true is simply breaking the law.
But if your constitution is incompatible with the treaties required to be member in the EU, you essentially have two options: change your constitution or not be member of the EU.
It's a bit more complicated than this, because the treaties don't really have any mechanism for unilaterally expelling a member state and there is no precedent for doing so. The reality is there is no easy answer to what happens when a national constitution is incompatible with EU law.
Member states can, in theory, be suspended, though we've seen when it comes to Hungary and Poland that mechanism is quite hard to use (as it requires unanimity of all of the other member states) and it's considered the "nuclear option".
Right now the political and economic interests of Germany and France is a strong EU. Won't always be true, though I can't foresee the circumstances when it might change.
Likewise, for most of my life, my personal political and economic interests included a strong UK (still does even though I moved to Germany) and USA even though I never lived there.