Comments on Valentines Day

A comment was left in my inbox concerning my blog.
...and i would say as a comment to your posting, that the reason most end in divorce (a bad conclusion) because they started for the wrong reason (lust, convenience, personal gain, circumstance, etc.) is there any more basic law than if something was started on a faulty foundation that it will probably eventually collapse? i would venture to say most if not all marriages that start for the right reason end the correct way--death.