Assalam Alekum my respected sister.
If you want to be rightly guided,you should consult Quran and Sunnah in this matter.We all are humans,we try to be kind towards our brothers and sisters in Islam but even we dont know our selves as better as Allah SWT can as He SWT is Aalim Al Ghiab.
My dear sister,i did'nt read all the replies but few and i can see that some brothers told you that they can forgive and forget such a thing and will accept a women like you but believe me,they are unable to do that.When Prophet Muhammad SWT,The one whose behavior is Quran and Who was sent down as a blessing, did not trust his beloved wife Ayesha RA for such a slander,then no other man is capable of doing this.We all love our brothers and sister,respect them and try to give them ease,but we are unable to change our nature.This is Men nature that he cannot forgive such a thing in spite of you are still chaste Mashallah and nothing wrong happened to you.
To understand my point correctly,you need to read the "Story of Ifk" in which,our chaste Mother faced a false accusation and which even confused and offend Prophet Muhammad SAW and He SAW did not believe in the chastity of Ayesha RA untill Allah SWT sent down a Ayah in Surah Al-Noor in which Allah SWT testify her chastity and showed His Anger on Mumineen as they did not help Ayesha RA prove it and called it a lie.
(24:12) When you heard of it, why did the believing men and women not think well of their own folk12 and say: "This is a manifest calumny?"13
If you are unaware of this story,you should read this.
http://qaazi.wordpress.com/2008/08/2...ry-of-the-ifk/
No matter what happened to you and about the sin you commit,this is a matter between you and Allah SWT only.Ask his forgiveness and he will forgive you no matter how great your sin is.But this is your responsibility to not open your private matters before people which Allah SWT hide by His Mercy other wise you will regret.Always remember that if you have your secret between you and Allah SWT only,you are the slave of Allah SWT only,but if you open it before anyone,you will become the slave of that person.
Never ever say this to anyone,not even before your Parents and your siblings.There is no sin not informing your future husband of what has done but it will be a huge mistake.As you said all that here to take advice,as a sister i advice you to deactivate this id after having your answer and do not give people your personal information.Id you wanna stay here,create another id.Always remeber that we all are humans after all and we might leak your secret.Love people,respect them but never share your secret with anyone.People forgive but they never forget and whenever Sheytan occupy then,they hurt others with their speeches and their acts.
Always remember that we all are sinner,but the worst sinner is he who open something that was hide by Allah SWT.Ask Allah to forgive you and He The Most Merciful will forgive you no matter how great your sin is.Ask him to help you and He SWT will help you like no other can.So put your trust in Allah SWT,offer Istikhara prayer to ask Him what to do next.If you have a proposal,He SWT will guide you whether he is ok for you or not.Trust Him Almighty and go with the divine guidance.Again never ever say all this before anyone in spite of you are blessed and rescued but keep it hidden always.
This is the best advise i can give you as this is according to Quran and SUnnah.May Allah SWT protect you from all bad people and bad deeds and guide you the best way and help you and never leave you alone.Amen.