A recent study by researchers at the University of Padua and the Max Planck Institute for Demographic Research (MPIDR) has revealed that political differences between partners can significantly increase the risk of separation. Using long-term data from UK couples, the researchers found that those with different party preferences were substantially more likely to separate than those with the same political beliefs. The risk is particularly high when there are differences of opinion on Brexit.
Your assessment makes sense, but some of the mismatched relationships mentioned here sound like they started out unbalanced, and that must be the case. Some couples are clearly doomed much earlier on.