I would say she is still having difficulty seperating the whole emotional side.. the differences between love and sex..
Its a daunting task, for some impossible.. When we ran up against this, i just explained it like this, suppose we went out, nice place, dance floor, DJ, or Band, if someone came up and asked her to dance, would she decline if it was Ok with me, and at the end of the night, its still just us.. regardless of who she DANCED with?
The arguement was but thats just dancing.. To which I countered, yes it dancing, and this is just sex.. Short term sex at that, like a evening dancing, or a day out playing softball or touch football.. There are no emotional components involved in those, If you can enjoy the FUN in the activity.
If you feel comfortable, with the situation and the person.. which can be a stumbling point.. why not go for it?