My parents marriage was annulled and it never crossed my mind that I was illegitimate. It is ridiculous on it's face to insist that I am bastard because my parents marriage was not a sacramental marriage. The only one calling people bastards is you. That annulment was a great comfort to my parents. It meant both of them could return to the sacraments. My father believed he had an obligation to try for an annulment so he could return to the Church if at all possible. I personally think it would be wrong not to at lest try to see if you can get back to the state of grace. I believe every divorced Catholic who has a desire to remarry has an obligation to see if they qualify for an annulment.
Oh sure you hear stories of people who are bitter because their former spouse wanted an annulment and got it. Why would that bother them? Would they rather be out of the Church or in the Church? Would they rather their former spouse be out of the Church or in the Church? If you don't WANT to even try for an annulment, you don't want to go back to the Church and evidently don't want your former spouse to either. What.... is it better to stay bitter, out of the Church and unforgiving of your former spouse? That does not seem very virtuous to me.