I have a dilemma which I know will probably sound stupid but I get a bit anxious about social things sometimes and overthink stuff other people wouldn't worry about so would appreciate some plain speaking advice!
A few years ago I formed a friendship with a work colleague, B. We used to chat a lot at work, go for lunch most days, travel home together etc. I was going through a very tough time with my then DH and B's friendship meant a lot to me. Anyway, a while later I left for a new job. We kept in touch for a time, but eventually it petered out as these things do - I had a lot going on, lost B's number, and changed my own, B moved and went travelling. This was nearly 4 years ago.
Which brings me to present: I started at a company this week where it turns out B also now works. I've been in for the last 2 days and looked out for B but to no avail. I did see one person who looked vaguely like them, but who didn't try and talk to me so I assumed wasn't. Plus I know appearances change in 4 years but this was quite a drastic change, so I wasn't certain enough to approach them myself.
I'm not sure whether it would seem odd if I ask one of my new colleagues where in the building B is based, especially if B hasn't mentioned knowing me? I'll also feel a bit embarassed if B is the person I mentioned, as they sit not far from me, I'd be worried if I ask that my new colleagues would take me over to say hello, which if B doesnt for whatever reason want to speak to me would be incredibly awkward 
So WIBU to ask?
Or should I leave it for fear of embarassment? (am tending towards the latter
)