All I can say is for a long time I felt like I was existing for everyone else but with time and practicing what I was learning at therapy I've been able to turn that around. It will help, it's hard work but things can change if you keep trying.
The other thing I want to say is, can you talk in cbt about how you handle your chronic pain? Your mental health will really affect your ability to deal with your pain which makes your pain worse which then affects your mental health. It's like a viscious circle and it sounds like you need help to break out of it. It's so difficult to break out of on your own but it can be done.