The advantage of marriage is that, if you make a mistake, you will learn about it immediately.
In nature all relationships are about give and take. The best one of course is a true partnership, a symbiosis of mutual benefit and the realisation of this fact.
Animals instinctively deploy stealth, cunning and aggressive brute strength to get their way and to take what they need or want. Humans on the other hand have a choice to do as all animals do, and much more, because we can consciously evaluate and make choices.
We humans because of our nature can over-analyse, so we have these concepts of good and bad and if one is religious minded than on believes in heaven and hell. Some clever people exploit this nature of ascribing guilt or sin upon others. Thus the vast majority of the population are busy atoning for some sin or offence in one form or another.
Guilt is so powerful that one can make the offender unquestioningly do the bidding of the offended. That is why manipulative and indecent people always use this to dominate the decent people.
Marriage is a social institution with the State and Religion forcefully locking two individuals together. The coming together of two animals with each one tending to control and dominate the other. Some do this subtly and some tactlessly. If one makes the other feel guilty, inadequate, or stupid then there is bound to be unnecessary tension and conflict.
Marriage is unnatural, nevertheless it has its advantages. When we allow our animal instincts to dominate, we lose most of the advantages and potential that a strong pair bond of a man and woman can yield.
Mistakes we all make, and no one likes to be reprimanded or worse condemned.
I have discovered a bit late in my life that the great value in a relationship is only realised when we do not so readily find faults or criticise others.