It Just Happened.
I got engaged early this year, and my fiance moved into my house, I got a job and everything was fine for the time being.
In my training group there was a man who made me happy, above everything else, he made me smile (coming to terms with depression meant this meant more to me than anything else) we got along well, he gave me lifts home and for the first time in my life I could talk about things that affected my life. He told me things that I would normally disrespect someone for, but it was different with him.
I noticed things at home weren't going well and ended the relationship.
On my work night out, in my drunken state, I made the decision to tell him how I felt, he couldn't make it out, his wife didn't want to go out. I told him at work, he'd been honest with me and now it was my turn. He felt, in fact feels, the same way.
I'm not a homewrecker, I wouldn't dream of taking him away from his children, and he's trying to make it work with his wife for them, I respect him for that. We still talk the way we used to, there's no secret between us of our feelings, but we're just friends.
Since then, I've got back together with my fiance, I still think about the guy at work constantly, but we're both trying to make the most out of a bad situation.
My point? Just because you fall for someone you can't have, it doesn't make you a bad person, it doesn't make them a bad person. It makes you human. None of us are perfect, and people need to realise that.