In general, birds will regurgitate to something - a toy, person, or other bird. So if you're seeing this, it's nothing to really be worried about.
But, just because she isn't trying to feed something doesn't mean she isn't regurgitating. My GCC regurgitated once after being badly frightened right after eating, and the day before she laid eggs for the first time, she started regurgitating food while just sitting on her perch - letting the food fall to the floor. I would have been very worried except that she otherwise seemed very healthy and she had been showing signs of being hormonal and about to lay (eating cuttlebone, ect.).
Another thing is, regurgitated food is generally nondigested (but usually chewed) food and I think vomit would be more digested. In regurgitated food you may find whole, hulled seeds and other recogizable bits if you feel like looking.

Another thing - regurgitating isn't always sexual. Siblings will often feed each other. Babies that are well fed will sometimes share with their siblings in the nest, and with many parrots some babies will stick around with their parents after they're weaned and may help feed their younger siblings.

Karen
Chico (conure) and Pippin (budgie)
WI

My GCC has only regurgitated a few times, but he does it when he is very very happy. After a good 20 or 30 minuets of finger tickling and tug-of-war with a string he can get very excited and throw up. If you can attribute it to a positive behavior I would say its nothing to worry about.