You cannot do nothing big about that. Just go and confront him and ask him. If he agrees it is fine and if he does not you cannot do anything about that either.
You have to have a prof. Otherwise it wont make sense.
You really don't unless you have proof, so you might as well be with him if you kind of trust him.
Only if you have proof. Maybe its a friend you may be mistaking and I have done that before.
you show her who is in charge and put her in her place
If a boyfriend is cheating with a younger sister and you and your sister live in the same house then 'the eyes have it!' This means they would be sneaking looks at each other or trying to accidentally be close to each other. If he seems to be in the same room as your sister all the time; may be in your home with your sister when you are not there. As far as your boyfriend cheating on you with someone else you would have to get proof of that and sometimes the proof comes from close friends of the two of you.
As i am a boy myself i reckon i wouldent like to be accused of cheating until you are certain they have cheated but if you have that proof best to just go up to him and ask not in a loud vioce but a quiet one
If I was in your place, first I would approach the boyfriend and tell him what I know. This gives him a chance to do the standup thing and confess. If he doesn't then I would try to get some proof to show her when I break it to her.
You either need a witness or proof of some sort before every accusing him of cheating and if you do then walk right up to him; look him in the eye and tell him how you feel and what proof you have.
He MAy be cheating, or it just may be your own insecurities. Keep your eyes and ears open , and don't say anything unless there is some marked strange behavior or some outright proof. Nobody like to be wrongly accused.
The Big Bang Theory - 2007 The Tangible Affection Proof 6-16 is rated/received certificates of: USA:TV-14
If you did not cheat then tell her to show you the proof. There cannot be any proof if you are telling the truth.
See if you could get some proof of cheating. Perhaps you can call some numbers you've found on his phone. When you do, figure out what you'd like to do from there. You would have to decide if you want to stay with him knowing what you do.
be as honest and sensitive as possible and make sure that you have proof that the person was cheating