Sorry you're having frustration with your co-worker, that sucks. I can tell you are trying so hard, and you don't need his temptations! But....I just wanted to throw this out there, from a third person perspective: I could be way off base but it sounds to me like this person just plain likes you. Could be romantic, but maybe not, maybe even just as a friend. Either way, the way he always was able to connect with you was through food. And now that's gone and he misses you..... but that's the only way he knows.
Like I said, I could be totally wrong, or I just always want to see the good in people. But perhaps his motives aren't to try to sabotage you (although it seems that way). And just remember, it's challenges like these that make us stronger!