Well it doesn't sound like you did anything wrong, but you need to see a business lawyer so you can set the business up correctly and protect yourself from preditors such as the ones you have described. Do you know if this is at the instigation of a nother party a competitior perhaps? Only a judge can sentence you to prison, not a lynch mob. This person who flipped may be the person behind all the trouble, you may need to get an attorney to get you a restraining order. Call an Attorney.
Every thing that I am saying here is my opinion and it is not based on any particular case. My response is just unsupported general information. If it helps you to resolve an issue that's great but do not rely on it as legal advice because it is not based on the facts in your case and it is not based on any specific legal research. Answering this question creates no relationship between the writer and reader of the writing. I am not your attorney now, nor have I been on the past.
It does not sound like you did anything wrong. I agree that you will want to have your business structured correctly so that you have limited liability to protect your personal assets from people like this.