As a man, I can only ask. Do women ever lie?. How do you know if a woman is putting on an act? A lot of good men have been destroyed by lies. A lot of women and men only show their true selves after marriage.
You watch the subtle signs of a person's character; his/her spiritual life, value system, morality, how he or she has lived his/her life, treated others and learned from their mistakes. Most communication is non-verbal. Words are nice but actions are more telling.
“Do women ever lie?. How do you know if a woman is putting on an act?”
Of course some people lie and put on acts. That’s why you wait for at least a year to get to know a person. You meet his/her family and watch how they interact. You go to premarital counseling and discuss issues under the guidance of an experienced priest, minister or secular counselor. If you’re not sure, there’s nothing to prevent a longer engagement. There’s nothing to prevent using condoms and/or contraceptive pills for a couple years after marriage if you’re not sure you’ll see the “real” person until the knot is tied.
I know that once in a while a consummate actor will fool everybody all the time, but if a person waited and went through the steps I listed, it wouldn’t happen often.