"My Mom ran the office for my Dad's business the entire time they were married." quote randman78.

This means your mother spent many years being "involved" with another person's business and affairs. This kept giving her permission to be involved in a way where she did not really have boundaries when it came to others. She got used to opening the mail and it did not matter who's name was on that mail, she grew to feel she had the right to open it. And, you also got used to her running things and knowing all about your father's business which is why you went along with her just coming to your apartment and having the right to know whatever you had there too. Your mother "learned" to know all about your father and his business as well as you and your business. It sounds like your mother really "ran" your father and you all her life, that is "her" normal so she is not going to think anything is wrong with her when she is giving her opinions to you about your life as she has always done that in her life.

Yes, you got a wake up call when you began living your own life. It is important to realize that "yes" your mother is not going to "know" how to let go of her control as she had been doing this for so many years. You know that saying, "Old habits die hard"? It is so true. And you are "right" no matter what woman you find and want to have a relationship with, your mother will find fault with her. Your mother will fault anything that she can't control too.

You have to be willing to see this reality and give yourself permission to break free of it too. And you will also have to realize that your mother is not going to like it either. Yes, your mother should have therapy, because she needs to learn how to "accept" letting go of that role she had always played in her life that she learned it was ok to have all that control.