It's not true that you couldn't continue seeing this girl. You could have. But it would have greatly angered your mother. You chose to stop seeing this girl in order to placate your mom. Until you own that, you cannot do anything to change your situation.

Until you realize exactly what you are doing and have been doing, you won't be able to choose to do differently. Sometimes life involves hard choices, where no option is a happy one. You want to be your own person in charge of your own life and be on good terms with your mom. It's going to be impossible to have both all the time. Life involves hard choices.

Also, you need to give your mom a little more credit for her own ability to survive. Her head will not explode, if you disappoint her. Her head will stay right where it is on her shoulders. You really believe that your mom just couldn't possibly cope with you becoming your own person. So you see yourself as making huge sacrifices in order to preserve her from what might destroy her. Maybe she isn't really that fragile. Maybe she can adapt a lot better than you believe. O yeah, there'll be drama and upset and all kinds of pleading and threatening and accusing you of not caring. She will make scene, after scene, after scene. Those "scenes" are not the end of the world. That's what you need to understand.

It's not your mom who is controlling you. It is your own fear.