I have this girl that i love to death and i dont know what to do... ive tried everything and i just need help.?

I have this girl that i love to death and i dont know what to do... ive tried everything and i just need help. I had to leave her for the army.. worst mistake ever..She was mistreated by some guys in the past and while I was gone a guy mistreated her again. .. im in love with this girl.. she is in love with me also.. granted she's 15 and im 19.. age is but a number.. she doesn't want to be mistreated again... it would be such a sad waste to trow it all away cause of her past.. everyone is telling me to keep at it and I've been doing just that for 3mths now..we've already had sex, kissed,hugged and all the above. . she wont show affection towards me cause she's says she's scared of giving into it.. what I gather from will determine if our relatioship will continue so please be as honest or as harsh as you have to be.. thanks