I'm afraid my girlfriend may still be loving her ex-boyfriend who broke her virginity. She has always proved that she loves me but I'm not convinced, even though she says she doesn't have feelings for him anymore. Is it true that ladies always have permanent feelings for men they first had sex with?

I really want to have sex. But, my boyfriend isn't ready and he said I could have sex with my ex who left me because I wasn't ready. I need to know if i should or not?