If you already given him a second chance, I think it is time for you to think if you still look at the future with him or else you might end up miserable while he enjoys playing with other girls. Find your worth girl, you do not deserve somebody you would cheat on you. Also think about it, if he really loves you, he doesn't have to do fling with other woman because he should be satisfied with you. Love yourself, find your worth. No woman deserve to be treated as a toy instead woman should be treated as a queen.

Are you objective with your recollection of the incident? When you are jealous or mad there is a tendency to be prejudiced that a small mistake becomes big in your eyes. If that is the first incident then I guess your boyfriend deserves a pardon but he will be under probationary. And if he repeats the offense then that's the time you can ax him. But for now, calm yourself and think of the good times that you spent with him. Or perhaps if you are really mad about it then ask for a cooling off period but not a break up.