@Hyena: I have no words for that. My simple mind can't understand how any god can be ridiculous enough to want you and your significant other to stay appart from each other just because he signed a contract that ties him with someone he's not happy with.
Why would any wise God want people to act in predefined, set-on-stone ways, when most situations in life are merely relative?
Mind you, sometimes the Vatican acknowledges that some marriages just don't work and allows said marriages to be broken, and both parts to re-marry again to other people...
I will start from the end - yes, the Vatican acknowledges etc, I have become a leading expert on marriage annulments these days, and will let you know, just in case you're interested, that:
(a) these days annulments are increasingly granted on the basis of fickle reasons, such as "immaturity" of one or both spouses at the time of the marriage, in order to limit the spread of civil divorce and remarriage; this is most frequent in the USA.
(b) However, if one looks beyond the work of ecclesiastical tribunals administered by men, the story is pretty much as i did tell it in the post above - if you are a christian you are going to believe that a marriage is a covenant between the spouses and god, not a mere contract, and you are going to believe that jesus said it cannot be dissolved, except when it is 'unlawful'. if you are a catholic, and accept tradition as living revelation, you will believe that a marriage is unlawful, ie null, when the consent expressed is not authentic or not possible (the latter case only refers to marriage among close blood relatives). this may depend on a number of factors: the most classical one concerns arranged/forced marriages, or marriages that were obtained by blackmail, such as "I won't give you this sum of money if you don't marry me", but it also covers marriages that were obtained by cheating on some quality of oneself, such as telling your prospective spouse that you do not have children from another marriage when it is not true, and marriages that were contracted while not believing in one of the fundamental contents of marriage (ie planning infidelity, or planning a complete refusal of progeny, or planning divorce at the first sign of trouble).
in my case, none of these held, eventhough there were elements that would have probably made an annulment quite easy, in a strictly formal sense. but we would be the dicks of the century if we just cared about that.
as to your first question, ie why god would impose such hardship, my technical response is "I have no fucking idea". If I knew fully, I wouldn't feel so horrible about it. i can grasp the human side - for example, wanting not to devastate his wife, who is already depressed and absolutely not wanting to be left by her husband. but i am not sure that this intersects 100% with the divine side. so back from the start - i have no fucking idea.