Well not to be contrary but: How do you know she just didn't hide her profile? Don't be afraid to communicate so that you both are on the same wave length.
In other words... if she agrees to "be your girlfriend" then you can tell her that you've already deleted your profile and what does she think about doing the same? If she doesn't agree to be your gf then you'd do well to put your profile back up and keep your own options open... don't keep your heart on your sleeve with someone who doesn't want to take down (or at the very least) hide their profile and stop logging on while you discover whether or not you've got enough to carry on together for the long haul.
Good luck.
“The willingness to accept responsibility for one’s own life is the source from which self-respect springs.” ~Joan Didion