Yes, cheating happens. Actually, it happens more often than we’d all like to think. The Institute for Family Studies reports that 20 percent of married men and 13 percent of married women admit to having sex with someone besides their spouse. Obviously, you know the telltale signals that your lover is less than loyal. But you’d be surprised what subtle behaviors might start to spell out the writing on the wall in scarlet letters… if you know to look for them, that is. From increased generosity to new hobbies, we’ve rounded up some habits and behaviors that could indicate that your significant other might stray, according to relationship experts.