I am really touched from ur story. Sweetheart, dont regret, coz whatever happen in 13, all happened coz u were too small and also you never had a nice childhood coz of ur parents. May be the present guy is right for you, But he abuses you and hurts u everyting .... hurts ur self-respect. U are not an animal. U are a Human being. Whatever happened is ur past and he shouldn't be digging it out everytime. if he does it ... he is wrong and someone cant be a right guy for u who does this to you.
Join some meditation centres, tell the instructor ur problem(not the whole story that happened, simply that u are highly stressed out coz of some incidents in ur past and u want to over come that and build a self confidence)... just attend the classes, i bet u will be really feeling better in just couple of weeks time. trust me!
And please, Just forget ur past present everything, no boyfrnd for some days, just concentrate on urself... love urself, respect urself .... and just warn ur frnd if he does that again to u gonna break off coz anyway there is no point in dragging this!
All the best! Just keep smiling and cheerful....