Dude, you are falling into the 'Friend Zone'. You need to read this post that I put out some time ago. Its not a question about being alpha at this point. You need to keep from getting into the 'Friend Zone' first and then work on your Alphaism. Cause once you are in the FZ no matter what alpha you are, you may never get out of the FZ.
viewtopic.php?p=313430#313430
I am assuming that you want to get into a relationship with this female colleaque.
Aside from the post, you need to make it clear to her that it would be better for her to talk to a woman friend about any 'guy' problems she might be having. If its about work, just listen and don't suggest anything.
Best,
J-Dub