Please help?!?!? (please read)?

2 years ago I was a succesful manager. Had gotten promoted and had been working in marketing for 7 years. Then a serious depression caught me. My boss talked to me saying that my productivity had fallen a lot. I quit my job. For a year I did something else. Started teaching english cles in an institute. Now I want to go back to marketing. But my insecurities have risen. I am insecure that I won�t be able to fullfil my job, I�m scared to meet new people and adapt to the new job. How can I overcome this fear?.....By the way: I have been in psychiatric therapy and am taking meds