I would advise you to focus on each moment. Not the past moments, not the future....the current moment. Simplify your thoughts by not allowing yourself to dwell on other thoughts. You are at work. Focus your sight, hearing, smell, touch, etc in what task you are working on right now. Work moment through moment. It really helps me a lot. Please do try it.
When times become too difficult for you to manage your depression, reach out to your pDoc or T. You need someone that you can be 100% honest with about anything, without fear of possible consequences.
I wish you the very best! Gentle hugs sent your way...