Your last line really struck a chord with me.:( I think that experiencing dissapointment, and when reality doesn't meet our expectations, are the hardest things to deal with as far as happiness goes.
However...the good news is that you are still in the game, and working towards your goals of recovery.
You can then expect that you will not be in this place forever. Look at how far you have come so far!
I see it. I read it in your posts. You are currently in a rough spot now...but everyone has those lows...
...and in general, I think that you have sounded stonger and more positive overall lately.;)
Keep telling yourself that you can handle anything coming your way at work, and that your lunch will be fine (with no incidents to dread), like it has previously.
Do not despair or give in my friend...you are on your way to good things.
Give your dear doggy a hug for us, and wish him well...I am sure that he will feel better soon.