Dude Get Life.....
Why always we blame girls for cheating? How many guys might have had sex with other girls beside their girlfriend?
why No body writes when guy sleeps with [Disallowed String for - bad word]ing other girls? And when girls do that it becomes big issue.

Its her life and its her body. She has all right to sleep with any friend of yours or any one she wants to before marriage.

Get a life dude.

About money...you gave her money as a gift. If she would have asked money from you as a loan ya she should return it to you. otherwise u r screwed.

You cant claim anything from her as u acted stupid.

Life goes on dude......Go look for another girl.