I think that in many times we miss on really amazing opportunities in life because we are so scare to appeare vulnerable. Actually we prefer in many case to be vulnerable and look all tough on the outside, then be really tough inside to the point of letting the vulnerability show.
It seem to me like this kind of behavior is what got you into this mess in the beginning - you were afraid to let the guy know you are into him, so you sort of played hard to get to the point of him giving up on you - and now, by being scared to "come out as pathetic" you are actually preventing yourself from having a chance with this guy.
Lets say he's not interested in giving you a second chance - which is, I guess the worst of your fears, then the worst that happens is that you found out where things are right now and can get on with recovery from the hearbreak and move on.
I think you have a lot to gain here and very little to loose aside maybe a chance little bit of ego hurt.
I suggest that instead of avoiding him at work or talking to him at work, give him a call one day and set a meeting in a neutral place and just talk about your feelings honestly and as openly as you can - whether he accept or reject you - at least you'll know where you are at.