When a horse is travelling nicely on the lunge, you want to be positioned as the tip of the triangle. So the lunge rein is one edge of it level with her head, the lunge whip should be pointed towards her hind quarters (when she is travelling well let the whip trail on the ground slightly) and you are positioned in line with her girth, just behind the shoulder.
If she is not wanting to move forward, you want to position yourself roughly in line with him hindquarters to drive her up more aggressively. If she is taking off, then position yourself more towards her neck.
As for getting her out. DO NOT let the lunge rein trail on the ground. Big time dangerous if she steps on it and it gets hooked around her leg. When she comes in, pull the lunge rein in with her to avoid getting caught up.
To get her out, you have done the right thing pointing the lunge whip at her girth/shoulder. If she will not move out from indirect pressure by just pointing, flick the lash of the whip towards her so that it flicks her shoulder/girth area. If she does not move away from that, walk purposefully and dominantly towards her shoulder/girth and flick the whip. If she takes off, no dramas, let her run as long as she moves away from you. You can fix the taking off later. If she moves away think of that as a positive. if she gets cranky, who cares, she's just putting on a show trying to get out of working, running around on a big circle is much harder work than on a smaller circle according to a lazy horse. So make her think the opposite, if she comes in towards you, it is might annoying when you run at her flickign the whip towards her, and when she goes out, you don't touch her, therefore being out on the bigger circle is far nicer than being in with you.