Hi Bella-
Your ex-friend sounds like Hyacinth Bucket in the old BBC series "Keeping Up Appearances" - always making people dive into the bushes at the mere sight of her!
The hardest part is that as she is regularly so close to your home, you are a sittimg duck for her visits/attacks!!! You might tell her that you do not accept visitors after work without an appointment- perhaps you could press her with sales pitches for the items produced in your business, often people seem to find that repellant!Izzy's ideas are quite good. You perhaps might also not answer the door for her when she knocks, or put a "Do Not Disturb" or "SHHH-Baby is Sleeping " sign up, play music that drowns her out, etc., ask her to pitch in and mop the kitchen, etc.
I also do not like to tell someone that I do not want to know them better or spend time with them on a one-to-one basis, and prefer to let my actions do the talking. Honest but not mean or arrogant.
Congratulations on your sucessful business Bella!
Love,
Changing