please try to give situation of your feelings, your confidence in your girl, love in your relation or make it more suggestive to your good friends
the perfect recipe to avoid this discovery.... a bit of jealousy (the good dose), full confident on them and on yourself ...and lots of talks
My ex done this to me a total of three times, the first two I forgave her,but on the third different story found a old girlfriend and turned the tables. Packed her bags for her to leave. Then the first girl I dated after the divorce done the same damn thing. For the next nine months I repaid the favor on every female never being faithful to one. Lost all confidence in young women not to mention so called friends who seemed to need all I dated.