Sexuality Confusion again :( !?

Right, i've already asked a question on here regarding my sexuality so it may seem familiar, but after reading some of the answers I realized I wasn't putting down the correct information as well as maybe not giving enough.

Firstly a brief description:

My close friends - known them or years and include my current girlfriend, there are 3 of us, all of them are girls apart from me :). Very tight knit, do not like others coming in unless they say so and they all hate the girl i work with - they mock her on facebook etc. but i am too scared to disagree with them too much. there are no secrets between 2 of us, all 4 (or them 3 usually) know and discuss amongst themselves.

Work Colleagues: weekend staff, there are 5 in total but 2 are my age (18) - the girl i get along with really well and would trust her with anything i tell her. The other is the boy that i fancy. We get along great however hes straight. Again, i would trust him like the girl i work with.

My work colleagues and I sometimes go out for meals etc. and my friends do not like this...AT ALL! They threaten to turn up etc but i like having this different group of friends from work, they have the same sense of humour as, which my close friends do not have.

Girlfriend andd her family: quite homophobic. comment that its nasty when they kiss on tv etc.

Right, now the "problem". I have been in a relationship with my girlfriend for 3 years. It is going good, however she has a very dominant role - basically wears the trousers. She takes most of her anger out on me, however she does apologise later in the day and i accept it however i still feel like **** and she does say hurtful things. She is very used to getting her own way too and is although she is very loving, she is very clingy. Says "i miss you" when we are apart for a day and insists i tell her i love her at the end of a phone call, even if its "where are you, i can't see you" if i'm picking her up.

Recently however, I have had feelings for the guy at work. I know hes straight however I cannot help having strong feelings for him. The other day he showed me a youtube clip at work and it was just me and him and i really wanted to kiss him! But i knew i shouldn't and didnt.

I am puzzled whether to tell him though. He is a very understanding person but i don't want to a) ruin our friendship (he is only one of 3 male friends i have, all my others are female) and b) make it awkward at work for me, him or our colleagues.

The only person i could tell is my female work colleague as she is so nonjudgmentalal and such a caring person but i couldn't tell my "close" friends because they would blab.

i just feel as though i should tell someone though as it does drain me emotionally. i saw a youtube video made by someone (strangely whilst looking for a Lady GaGa song) which was saying about gay relationships and had pictures of what i would say "real" gay men - not porn stars - hugging and kissing, and it made me feel so upset it nearly bought me to tears because i felt as though i wanted that (not necessarily with the guy from work) but it will never happen.

Hopefully this is clearer and thankyou for reading this, i do waffle on i know!

So again, THANK-YOU!

Btw, no gay-hating comments please or comments about how God and you believe its wrong, if its that wrong then why are you browsing questions in the " Lesbian, Gay, Bisexual, and Transgendered" section anyway!