How to walk out of your marriage and feel no guilt

When Brad Pitt walked out on Jennifer Anniston and flew into the arms of Angelina Jolie, he probably experienced at least a little bit of guilt. That is because he fell for another woman while married to his ex, even though, by the looks of things, his ex is a perfectly nice, all American girl (and was his best friend!) I often observe how Brad’s aged so rapidly in such a short space of time, and I’ve always wondered if it is guilt that is eating him, or whether it’s the strain of caring for six kids that is taking a toll on his beauty naps. 
The way you end a marriage or relationship matters, I think. I mean, how do you go home and tell your other half that you want a divorce, knowing that the reason for this is that you found a more shaggalicious substitute, even though you were careful to tell your shocked, heart-broken spouse “there’s nobody else, this just isn’t working?” The thrill of greener pastures notwithstanding, that must bring on at least a little bit of guilt. And I’m not saying that to judge him or get into his business. I’m just saying that the way we end relationships will factor into the emotions we feel in the aftermath. That’s true for all of us, not just Brad.
It’s not the act of asking for or getting a divorce that gets most people. At least, I don’t think so. It’s how they do it. In order to emerge from a marriage in a peaceful place, I think it is necessary that, first of all, you are completely honest and transparent with your spouse.  Sometimes, the marriage simply does not work. Two people go in with the best of intentions and they just couldn’t pull it off for one reason or another. That’s fine. It happens.
What is not so fine is starting to look before you end things with the first relationship. Allowing yourself to “fall in love” with someone else when you are still married to your spouse is not okay. At the end of the day, that’s my grand conclusion. I don’t think that is okay. I think it will get in the way of the new relationship eventually. Because your hands are not completely clean. The new relationship is not planted in pure soil.
And I am not trying to sound puritanical because I am a far cry from that, and you know what, I am old enough to know that life can get messy sometimes. I also have come to accept that not everybody is married forever like my parents. Divorce is reality. For crying out loud I am a divorce lawyer of all things! But I think the only way to walk away from marriage (or relationship) with no guilt is with a clean, clear conscience.
Knowing that you have given the marriage everything you have to give will buffer you against the guilt, if you eventually decide that your best was not good enough for that particular union.
If there are children involved, let them be free to be with the two of you equally, or as much as possible. Do not use them as pawns.
If you do this, in this simple way, I think you will be able to walk away from the marriage with little or minimal guilt.