Ok well start talking to the one you are not interested in on an anonymous account and copy everything they say and send it to the other person. Online stuff can put real doubt into peoples minds. I mean I just recently had seen a convo between my boyfriend (idk if we are dating still it happened today) and another girl online and it was not innocent. I did not flip on him and he keeps acting like it never happened but I have doubts as to whether or not we are going to stay together because this is not the first time I caught him doing stuff like this and yea online convos can ruin a relationship real quick. put all kinds of doubt into someones mind.