LC - I think the woman is probably mostly straight but more bi/loosened inhibitions. The whole kinsey scale and how many (perhaps most) are not completely straight or gay.. It is not a serious act with most straight women who do this, in my experience of it.
The Kinsey Institute - Kinsey Sexuality Rating Scale

It might be prudent to reconsider going out drinking with coworkers right now. Maybe dinner or happy hour with a group, but not alone with one and not a lot of drinking.
LC - don't sabotage yourself like this.