Marriage? His marriage scarcely existed. As soon as his wife gets pregnant and he is forced to come to the reality that marriage is not all the bliss of a honeymoon the marriage deteriorates rapidly.
I would say the reason for this is because of a skewed worldview. Ivan was out for his gain, and his gain only. He married her because of her looks, family, and money, not because of a genuine love for her virtues and personality. A marriage has to be a give/give relationship for it to be a gain/gain relationship, but Ivan imagined it as a gain/give relationship (Ivan doing the gaining of course). This same worldview that the world is out to hurt him and he should be always on the defense is the cause for many other failures in his life.
Worldview is just as important to marriage as it is to any other activity of life, and Ivan's worldview is what gave him a very unpleasant marriage.