How do I stop my crush on this guy at work?

At first I thought it was a harmless crush but now I find myself trying to look nice for him all the time before I go work and being disappointed when he's not there and going through his Facebook constantly.

I feel like a crazy stalker but I manage to play it cool in front of him and just tell myself all I want from him is a friendship and I just enjoy the attention he gives me.

He's extremely attractive and all the women have a crush on him at work. He even his a girlfriend at work but he chooses me to talk to constantly over her which I find odd. He's always running over to me at work to tell me something about his day and he doesn't have any other female friends at work besides me so I guess it makes me feel special but someone so attractive thinks highly of me.

he's also super rich and super humble about it too, he has a really cool life outside of work and I guess that's why people find him attractive too.

But I have a amazing boyfriend who I love very much and I feel like the worse person in world for liking this guy. He knows I have a crush on him but not to the extend that I do now before we used to just joke about it.

Me and my boyfriend have been together for 3 years and in that time I've only had eyes for him since now. I never found anyone else attractive but him before I met this guy.

I'm definitely not going to cheat or leave my boyfriend at all he's too good to me and sometimes I feel I don't deserve him. He treats me like a princess and he still manages to be a carer for his vulnerable family members and run a business and charity.

It's just 3 years isn't the same as the relationship was when we first started dating. Now we're to tired for sex and barley have it and were just like a married old couple.
How do I stop my crush on this guy at work?
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