Assalaamu alaikum, my dear,
(gently) I am very sorry to hear what you have suffered, and how you continue to suffer. If you were a child at the time you were molested, and furthermore, you didn't even understand what was happening... how could you have "a past"?! You are innocent.
You mention "and less serious stuff"... no, any time someone takes sexual advantage of a child, it is always serious. And if there was a deep bond of trust (if the person who abused you was an adult in a position of trust)... then the breaking of that trust is a deep hurt in and of itself.
Furthermore, even if you were not afraid of being beaten... even if you had been taken advantage of through pretty words and offers of treats, to gain a semblance of agreement... you are not responsible. Because this is a manipulation by an adult of a child.
(gently) My dear, you are pure and clean. Please do not burden yourself with the feelings of shame and guilt that rightfully belong to the man who hurt you.
As for disclosing what happened to you... this is up to you, my dear. If you want to seek counselling, then do so. If you want to tell your future husband because this is something that is causing difficulties for you with intimacy, then this is something you can do, if you feel that it is appropriate. If you want report the person who harmed you to the police (to protect other children...?), you may do so.... And if you do not want to talk about it (at least for now- you can always change your mind), then don't. (gently) You have been forced enough.
Again, you did nothing wrong. You did not sin. You are free and clear of what happened. Indeed, the fact that you fear to displease Allah so much that you are so worried about having done so... (smile) says to me that you are a good and decent person. So hold onto this goodness in you, and let go of taking responsibility for this man's misdeeds.
May God, the Gentle, the Loving, Enfold you in His Care.