How common it is for Indian men to cheat or to be in affair?

Please don't get me wrong. Unlike some girls who claim 'I hate Indian men' or give stupid advices like 'Migrate to another country and marry there to have a better life', I am totally against all that and with all due means, I respect the men of our country. But I am asking this for a different reason. Lately, found that a acquaintance of mine is getting cheated, confronted her and told her all about this only to get lashed out by her that I am jealous of her and trying to break her apart. I didn't have any evidence to prove what I said but she could have at least paid heed to what I said to an extent but she was too naive to understand it. I am too hesitant to take pics to prove it to her since you know, that sounds like dragging yourself to an unwanted problem and hence just thought of giving her an heads-up. This is a personal incident that I was involved in. But there are numerous cases which is going on in and around me like this which I tried to ignore after understanding that approaching the victim and trying to make them understand is something which isn't safe to do since most of them blindly trust their partners. Talked to a friend of mine and she kinda said the same thing and adviced me to stay the hell out of all this and not try helping them since most of them are not cooperative or open-minded enough to listen to accusations like this. So, yeah, asking it here now to get a bigger picture.