Guy's Behavior

I'm worried of ruining a friendship between Me and this guy at work?

It all started when he approached me at work about 5 months ago. He was asking me if I'd started training yet as he hadn't, after that he kept trying to make conversation with me but I was really shy especially because I thought he was really cute.

I knew he hung around with a girl at work but I thought she was his stister because of how they acted together.

A couple months later we ended up training together. Turns out we had loads in common and we actually formed a very close friendship.

He told me the girl he hung around with was his girlfriend but as time got on and are friendship grew I noticed him distance himself away from her more and towards me. He'd eat lunch with me when she was in the same room as us, I thought maybe they didn't want everyone knowing at work but they were together.

Recently I noticed really strange behaviour between them and thought something might have happened.

I'd try to avoid this guy as I knew my feelings for him were wrong and unfair to my boyfriend.

Today he came to eat lunch with me and my best friend at work. I tried to not pay much attention to him. He's a lovely guy don't get me wrong but it's for the best. As I was sitting with my friend she was showing texts she'd shared with a manger she likes at our work. She really likes him and wants a relationship but wants to keep her options open just incase he isn't interested.

After lunch this guy started asking me about my boyfriend as he was interviewed for a part time job at my work but he later decided it wasn't for him. I told him this and he said it's probably for the best as it can makes things awkward if we break up and then mentioned he broken up with his girlfriend and that he was now single. My face went bright red and I started to feel sick as I was really scared what was coming next.

I rushed to tell my friend the gossip and at first we were both sad for them but quickly after she said "he's fit I might hit him up on Facebook" which she did.

Updates
+1 y
I'd like to throw out some key points as I know a lot of you don't read questions right... including myself

. have a boyfriend who I love very much and would feel physically sick and never be able to forgive myself if I ever hurt him so I'm definitely never going to cheat on him. would never cheat and I hate cheats.
There's a guy at work I'm attracted to and I've not been physically attracted to anyone else since I met my boyfriend 3 years ago. I have encouraged my friend to try and date him
Updates
+1 y
So sick of people not reading the question right
I'm worried of ruining a friendship between Me and this guy at work?
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