<human>: My friend was dating my other friend (I met them at the same time) for four years.  I've known them for the past three years.  Over the course of these three years I've seen her treat him like shit, repeatedly, and every time something happened between them all of our mutual friends would suggest to me that we should date each other instead of her being with him.  However, also through the course of these three years I became one of her best friends and would try to give her advice that would work in both of their favors.

The current situation is that they've finally broken up.  She is dating another person in our friend group.  Now that they have broken up, I've been thinking about him a lot and that it would work.  We both feel a strong connection with each other and there is a lot of chemistry between us.   

I feel really conflicted as to whether I should pursue this or not because I am her best friend and don't want to betray her.  One of the other girls in our friend group, who is not that close to her, hooked up with him a couple of times and was flipped out on.  

There is one final thing to mention which is, that when this guy and the girl were in a relationship but on the verge of break-up he had feelings for me and she encouraged him to share.  He did tell me after her pushing him to, but I was in a relationship with someone else at the time.

Could you distill the essence of the text into 1-3 sentences?
<bot>: Best friend and best friend date for four years and then break up.  I have feelings for him, and he has feelings for me.  Don't want to betray best friend so confused as what to do.