But sometimes things they have done before, which they are violently withholding from each other, don’t even let the marriage get started and forty-eight hours later their marriage is on the rocks because there is just too much overt and withhold before they even knew each other.

Make this lower case.
but sometimes things they have done before, which they are violently withholding from each other, don’t even let the marriage get started and forty-eight hours later their marriage is on the rocks because there is just too much overt and withhold before they even knew each other.