Antonyms for the phrase "doing business with" would include many negative connotations such as unethical behavior, avoiding transactions, or simply not having dealings with that person or company. Possible antonyms for "doing business with" could include cutting ties, severing relationships, terminating cooperation, or disassociating from the individual or organization. These antonyms imply that the relationship between the parties has reached a point where trust has been broken, values have been compromised, or the benefits of continuing business activities have been outweighed by the risks. It is important to note that these antonyms do not necessarily imply hostility, but rather a business decision to part ways.