As I'm sure you're aware, targeting chicks at work has become even more of DANGEROUS MISSION than it already was. You say that both the girl you're currently dating AND this new women are both "work" chicks.
Let me tell you something that you already know---just for the sake of a reminder:
EXPAND your horizons and broaden your field of vision so that you will begin noticing women in other environments that you're attracted to.
In other words, make it your mission to abandon the sniper approach to finding women and adopt the shotgun approach.
Also, be aware that PROXIMITY can sometimes become a prescription for confinement, a prison---or a "Thirst Trap", if you will. If you are finding that you have fallen prey to limiting your exposure to eligible women to "only" your place of work---know that you have limited yourself FAR TOO MUCH---and you are either setting yourself up for romantic relationship self-sabotage (at best) and/or "approach-laziness" (at worst).
Understand that women are EVERYWHERE. There are so many places that you can find women (other than work) that you would be AMAZED (once you get out there and do some REAL reconnaissance).
From what you've written in your original post, you don't seem to be very enthused, engaged, or excited about the chick you're with right now. And if my assessment is correct, then I would say that it is a very HIGH possibility that you've already "settled" for LESS than what you want in a woman (especially if you're willing to risk it ALL by approaching yet another woman at the SAME place of work).
I would recommend that you start being MORE true to yourself, and eventually true to that woman you're currently with--and begin to REALLY go after the kind of women that you really like. Sure, there will always be women who are more or "less" attractive than any woman that you eventually get with---but I submit to you that you will STILL find that the level of temptation to hook up with random chicks you see from day-to-day will markedly decrease.
And again, by all means---expand your dating pool to beyond your work environment ASAP. Because unless you ARE really happy with the idea of a woman who you're dating (who is also working with you in close-quarters)---then understand that it's usually only a matter of time before the sweetness turns sower, and then that bitter taste may begin permeate not only your love life and your personal life---but your WORK life, as well.
So be wise.
Always think several steps ahead.
And look out for your own best interest AT ALL TIMES (---and that means mentally, emotionally, sexually, AND FINANCIALLY.)
If you successfully accomplish the mission I've outlined for you above:
I guarantee that you'll be THANKING yourself profusely for having done so in the future.
V.U.
