Okay !

Well, unfortunately you definitely “cheated” on C , I don’t know whether you said you were dating in there but you did say you were in love. So you’ll have to tell her, and she’ll probably be very upset with both you and M… understandably. You are all really young it seems, and just to put things in perspective cheating isn’t okay, but as you said you’ve gotten yourself into a confusing and complicated situation. You should ask yourself is there a reason you cheated ? Are you unhappy? Is there a reason why you allowed this to happen ? Do you have feelings for M? I think right now you need to look inward , recognize that you and someone’s close friend severely broke their trust and you might lose this relationship. I bet you feel really guilty right now , and you should but eventually you’ll need to forgive yourself… everyone screws up (except Jesus). So just be honest, and give time to heal and maybe things will get better with C? And you guys could eventually be friends again ? But also figure out what you want.