You certainly know what to do but you just want the feeling...you are embracing the unwanted. Even if we all know it's wrong you will eventually do according to your strength. It's so exciting to sin is it not? But can you live with the guilt and with sleepless nights? If you do not have God then probably you will be swept away by this trial, but if you have good reason to fight this unexplainable thing which not only you nor me nor some might experience...then nothing is impossible. Ask your self, who the hell a good person can ruin a married life? If you have reason such good reason to leave your partner say punching and hurting you..well then you may. But if you were just lusting to be in love not loving to be in lust...then you may be wrong...tell the person who bothers you not to anymore if that is tha case...and tell your self there are things which are more important in life you shall keep the flame of love and attachment to the one that you marry, other wise we all be CHAOTICALLY gone wild looking for the missing part that just need to be worked out within our partners...
It's part of married life, it's a stage of coping, learning, and living...important thing is...you knew what you want and you will fight for what is really just! and at the end of the day whatever you will do and plan to do there will always be consequences.Good luck and may the Spirit of Godly judgement be with you!