How to deal with my GFs past?

I love her and she sees me as her future husband she has had a threesomes and just is over all experienced, she tells me that I'm the first to make her orgasem witch I believe that's a lie over all it plauges my mind the fact that it'll never be anythibg new with her and the fact she's not as sex drivin as I am prib because she has experienced it all and now I'm one to suffer. I know it sounds bad to you girls but idk it just sucks. She doesnt deserve a guy that can't get over her past so my question is to guys who felt they way I do NOT GIRLS have you gotten over it?