He is taken. How do I not fall for him again?

[Paper]

Last summer I fell for this guy at work but he already had and still has a girlfriend. They have been together for several years and I know that I shouldn't have feelings for him. Nothing between us really happened. I went to study abroad and started to get over him but we started writing a little over facebook and the old feelings came back to me. After a while I decided that I needed to end it and straight out told him, that I liked him and that we shouldn't spend time together outside of work. It turned out that he also had had a small crush on me. Needless to say, it made me very happy and very sad. He is not a cheater. He never made any kind of move on me and we didn't message that frequently.
I'm still studying abroad and now we don't message each other at all. This is how it should be. I'm quite proud, that I was responsible enough to stop what little contact we had. The thing is, I'm still not entirely over him and we are gonna work together again this summer. I'm scared that I'll fall for him again. I won't act on my feelings, but I'm scared of being in agony over it again.
I just wanna stretch that I am NOT hoping for us to become a couple. I don't plan to steal him and I don't see us being anything more than just friends, if even that. My question isn't "How can I snatch him away?". I want to know how to keep myself from falling for him all over again. So please, I know I have to move on. My question is how.

[delightfulflavor952]

B*tch, leave him the f*ck alone.

[tagboy]

You best come to terms with him just being a friend. Time you started looking for the right mate, if there is one.

[Gena Smith]

Look, he is stable with his gf and if he didn't leave her for you last time, he is not again. Look, at least he is decent and you are decent. I say move on and there are plenty of guys, you are just focusing on one tree in a forest.

[Renee Riggs]

The only way to be sure not to have a situation trip arise is not to work together, i guarantee if you do those feelings will still be there probably Stronger

[Bεεbe ❀Tяee]

You should be proud alot of people would follow their lusts and ruin a long relationship ... I think that as long as you don,t talk to him too much..like keep it extremely casual if you have to just avoid him... or check out someother guys..there are more *available* fish in the sea that'll be as loyal to you as he is to his gf .