he has.
I think we're not giving him enough credit. He did realise that a relationship is impossible and he did move away and try to distance himself from her and he did date women his own age. I say kudos to him for doing all the above. He sounds like a reasonable, intelligent guy.
What he's asking is why/how did this come to be?

And it's really hard to answer that. Sounds like one of those things even experts are still arguing about. My guess is you just got attached to her through talking to her. As you said, brotherly/fatherly kind of love. At this point I get a bit confused- did it morph into romantic feelings? or what made you leave? Don't worry, you are not a perv; you didn't do anything inappropriate. the feeling could just be a "natural"/"primitive instinct" type thing; On an evolutionary timescale, a 14 year old girl is a fertile female who will probably only live till she's 30 or 40. Having said that I want to make it clear that I do NOT support inappropriate behaviour towards minors, and I certainly I find people who take advantage of teens are despicable. I am just theorising about your question of why you have these feelings. Even if she was 18, I would still advise you to steer clear out of respect for her father. Maybe it would help you to talk to a therapist?

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