What would you do if your boyfriend/girlfriend kissed another girl/guy in truth ot dare?

he broke up with me. he said it was becasuse his mom didnt want to see us together..later at the same day he saidhe felt dum and wanted me back. he said that the true reason he broke up with me was that he didnt want to see me get hurt. he said him and his friends were playing truth or dare and they dared him to kiss another girl and he did. i was really hurt when he broke up with me and i am still confused. i said yes when he asked me back, but im not sure if i feel the same way for him since then. i do love him and alot but i dont know if hes worthy of my love....should i forgive him or break up with him.. what would you ppl do in this situation?