There is no way for future husband to know or not know you have had sex unless you tell him.
I assumed India or Saudi Arabia, but still ... she says she is an independent lady. Does that mean she could live without being married, or is this something where she is being literally forced?
In some other countries they do have arranged marriages. I'm wondering if that's the situation here?
How can they force you to marry someone? If you are an independent lady (enough to refuse to beg your boyfriend to love you again if his interest has cooled, and I don't blame you for that!) why do they have the power to make you marry someone else? Life in a bad marriage is a lot worse than life alone, especially for a woman who can take care of herself financially.
Are you saying the boyfriend you've been with for 8 years is the one you're supposed to marry? Or, are you saying you were with him but he broke up with you and now your parents are forcing you to marry someone else? I'm sorry, but I'm confused.
If you mean your future husband is another man who your parents chose for you and you don't want to tell him you've had intercourse before there really is no way to hide it unless your future husband is a virgin. He probably would not know the difference. If he asked you though, the right thing to do would be to tell him because no marriage should be started off with a lie.
If I got any of this wrong please forgive me.