From someone who's been there - and occasionally starts to head back there - I offer sincere congratulations on (1) recognizing it and (2) speaking about it both here and to this new person in your life. That said, I cannot stress enough the value of a good counselor and possibly medication to help get things on a sustainable, healthy, enlivening course.

(For me it took some meds to help give myself mental space to begin forming healthy habits and ways of thinking. In case it helps: that first pill was literally the hardest thing I've ever had to swallow, because at the time I thought it meant that I couldn't fix myself. In retrospect I realize that choosing to take meds was in fact me taking control.)