Dear Momo, you're an addict and hey - that's what addicts do. Stick with Duvid Chaim's calls, keep reading the amazing advice in the daily chizuk e-mails from Dov (the past few days especially), flex those "outward-focus" muscles more and more, step by step, over time - and you will start to see a HUGE change in yourself. If Dov can do it, why can't you? Dov was much more addicted then you, and to worse things. And he's clean 11 + years.
As far as work, I liked Uri's advice. Swear to yourself (say, for 2 weeks at first) that you don't act out at work, period, not innapropriate images and not mast**. Whent he urge strikes, promise the Yetzer Hara that as soon as you leave work, you'll do whatever he wants, but NOT AT WORK, period.
Hopefully, by the time you leave the urge will have died down. (But don't think about that when feeling the urge, just say "later".)
Can you do this?