Just let her be. Eventually she'll come around once she feels safe. I had a feral kitty, LilEli, who wouldn't let me hold or touch him. I let him be and eventually he started coming up on my bed (the supine position is the least threatening to a cat) looking for pets. It took 3 years and he was still skittish.

It takes alot of patience to socialize a feral kitty, especially one who is 8 months old and feral. When she flops on the floor and exposes her belly, that is a sign that she trusts you, but not enough for you to touch her. When she does that, sit on the floor with her and toss her treats, speaking softly to her and slowly blinking your eyes.

You COULD get a crate and try to crate her. Take her out and wrap her in a towel with only her head exposed (it helps protect you from getting bitten and scratched) kissing and whispering to her. Keep doing it. She may come around sooner.

I hope she eventually DOES comes around. Be patient. It won't happen overnight or even in 6 months. It may not even happen at all. But ya know what?? That's okay. Cuz she's got you to care for her and she's safe. That's what counts.

Good luck and keep us posted.