<human>: Ok, so I'm just throwing this out there for some advice on what's really eating me up right now.

 I'm in a happy relationship (20 f w/20 m). We've been together for 2 years, and we really are quite great together. Hardly ever fight, his folks even took me in when mine kicked me out. 

I don't know why, but I'm dwelling right now on someone I hurt quite some time ago. About a year and a half ago, I had this big crush on a co-worker. We were friends, but I had pretty strong feelings for him. I knew that I would never cheat on my bf, but I couldn't help but wish I could pursue this guy. Instead, I basically acted super bitchy to him and unfriended him on fb, (immature, I know), in order to remove myself from the situation.

I don't know why this is resurfacing, but I feel so guilty for treating this non-boyfriend guy so poorly. I really want to shoot him a message or an email explaining my motives, but I'm not sure what's to gain there. I want to assure him that it wasn't anything he did, this guy is the lonely type and very cynical. Hell, I'm probably fooling myself that he even cares anymore, and I probably shouldn't either. Advice?

Can you succinctly summarize the text in 1-3 sentences?
<bot>: I want to explain myself to an old friend who I basically shunned after I couldn't shake my feelings for him while in a relationship. Should I, or is this just pointless and I need to forget about it?