A long distance cheater performs pretty much like every other cheater, except it’ll be harder to catch him or her in a lie. Watch out for the following signs: They don’t want to talk to you over video message or on the phone.
They might respond to your written messages, but pay attention if they’re reluctant to talk, or see you face-to-face screen. If they’re lying, it’ll be much easier to do it in writing since you can’t see where they are, You start to see an abundance of new friends pop up on social media, usually of the opposite sex.
Pay attention if you start to see the same person pop up in group shots or see a banter exchanged between the two of them on social media They haven’t acknowledged your relationship publicly i.e. on Facebook. Slow communications, it takes them days to respond, and when they do the messages are short and impersonal
2. To me there’s almost no way to find out. They can cheat on you and still do all the things for you that you like and you couldn’t find out. Maybe one way would be that they are not interested in calling you /skyping with you as often as you guys did, or they just tell you they are not sure when they can see you again or they postpone everything related to you two.
Whatever the case is, your option is to trust your partner (because, basically, this is what a LDR is all about). If you have serious doubts, find a way to talk to your partner about the issues that are worrying you (such as cheating), and discuss your options in case one of those issues are putting the relationship at stake.
3. There is a sudden and persistent change in his or her behavior or communication patterns. They are often unavailable to take your call on a moments notice, and seem to be perpetually busy—they have many evening, weekend or holiday commitments. They seem perpetually rushed and harried whenever you contact them,and only ever relaxed when they contact you, at a time that suits them. They rarely talk to you from home..
They usually call you on the way to or from work, or during business hours. They always want to come visit you,rather than having you visit them. They won’t acknowledge your relationship on Facebook or in other public ways. You know they have a history of cheating in past relationships (Please Note: This does not mean that they will cheat on you, but bear in mind that past behavior is one of the best predictors of future behavior.) They frequently talk of someone in particular, and of time spent alone with that person. Or they talk about a whole new group of friends they’ve suddenly started hanging out with. They don’t seem eager to introduce you to these new friends or to other people in their lives.
4. When he acts different than usual. When he thinks its all about him and refers to things that only has to do with him. When you ask him a question about what he is doing, then he answers you with another question.
When you tell him you love him and he hesitates to answer. You catch an STD from him-disease -sexually transmitted. Too many calls from a family member.Go through his mobile for these numbers when he is in the shower.