There is obviously something wrong in your marriage for your partner to have done this. You both need to talk this through, if you love him deeply then I would say yes to giving him another chance, however, if he does it again, its time to close the book on your marriage Im afraid, now this is also going to sound harsh and forgive me in advance, but for a man or a woman to 'stray' there are problems from both sides, I dont think you can lay the blame on him, sit and think why he has done this...it could just be for sex which men can do easily without emotion. Its very rare for a man to leave his wife for the 'other woman'. Good luck and I wish you all the best and hope it works out for you. xx