girlfriend cheats with co worker

a week and a half ago my gf cheated on me she met this guy at work and gave him her number and he wont leave her alone. it takes all the strength that i have to not go and beat his face in. but i know it was on both of their parts. i just wish when life has you down it didnt kick you in the face to make you fall harder. i love her with all my heart and i have to swallow all my pride just so i can stay with her cuz she makes me happy. i now live day by day. just praying it doesnt happen again. if you read this before you deside to cheat remember one thing if you dont have the balls to break up with some one then you dont deserve the other person. because weither you like it or not that other person is never going to be what you think they are. as my heart sinks in the abyss i can vouch with anyone and sypthise with them too. this is deffenitly one of the worst feeling i have ever had. and then she had the nerve to come home and sleep with me in my arms kiss me on my lips. i just want yall to know there are honest people out there just good luck finding them