<human>: m/f early twenties, I am the f.  In a LDR but close enough that we see each other every month.  The relationship is two and a half years old but we lived together for nearly two years of it.

This is my first serious relationship and when I lived with him, he was pretty much all I could see.  I didn't find other guys attractive, except fleetingly on the street or something.  

I've started working in an office where I live and there's a guy I get on with really well, let's call him Eric.  Eric and I talk and laugh a lot of the time, we have some things in common (but not nearly as much as me and my bf) but he is a lot more talkative than my boyfriend.  I have complained to my bf - let's call him Sid - about how few real proper conversations we have. Sid says this is because we aren't just starting out now, we're comfortable together and we aren't learning loads of new stuff about each other.

Don't get me wrong, Sid and I do talk, and it's only really a minor problem.  I understand his counter argument, but it's just been thrown into sharp relief by how much I talk to Eric.  In addition, I find Eric quite attractive and find myself accidentally eyeing him up.  I don't actually fancy him, I have no intention and do not really want to do anything physical with him, and I don't think I'm emotionally cheating because he and I aren't even close to best friends, I don't tell him much about me except generic things like what kind of films I like, but I am aware the things we say and do could be classed as flirting and I'm worried I really shouldn't be.

Like I said, I don't fancy Eric.  He has a girlfriend and he is fully aware I have a boyfriend.  I love 'Sid' and have no intention of cheating on him with Eric or anyone else, ever.  I'm just worried I'm doing something wrong and/or that I should tell Sid about Eric.

I really don't know what to do, I have literally never been in this situation before.

Can you condense the text into three sentences or less?
<bot>: LDR, made new male friend at the office.  Concerned I'm flirting with him, don't know what to do and if I should tell boyfriend.