Work on making her leave you when you ask, stay at a distance of you that you decide, and come to you when you ask again.
Use a small fenced area or a long leadrope.
Start with waving your hands and arms to make her back away; if she oesn't react, do it more agressively and walk towards her. If she overreacts, be calmer next time. Stop as soon as she moves away, and relax.
Walk away when she's at a distance and let her follow you, but stop her if she gets too close and back her.
It's to make her respect your personal space. She shouldn't come ''in'' unless you allow it (by inviting her with a relaxed body and calm mind) don't get mad but make sure she's never too close to you if you avn't allowed it.
YOU approach HER most of the time, or at least call on her.
Listen to her body language and learn what she say.
When she bumps you it might not be mean, but it is carelessly and she's saying ''I don't have to care about if you're there or not''.. make sure she cares ;)
Of course don't scre her. But she'll feel better if she know you're a strong person, since you make a lot of decisions for her.