[spoilers] Harry and Ruth. The Wonder Years.

[Belle]

I rewatched 8.4 yesterday and, when Ruth and Harry sat on that bench to talk about Jo's death, there was already a feeling of rejection by Ruth. I got the feeling everytime Harry tried to get closer to her, she warded him off and changed the subject so she wouldn't have to deal with their feelings for each other.
Don't know if, at that moment, it had to do with Ruth still being angry at Harry for what happened to George or if it was an indicator for the fact that she would eventualy say 'no'.

Also, when Harry answered to her question if there was something else, he said 'there will always be something else' (or 'more'; sorry can't remember the exact word), I didn't know if he ment that he understood the way Ruth held him responsible for what happened to George or if he thought about the unspoken feelings between them.
Maybe Ruth ment, when she said 'we couldn't be closer than we are now', that because of the work they do and all the grief they share (for colleagues, for the evil in the world,..) they have a bond wich goes very deep and is very strong and if they would resign and just be together, maybe she is scared that that bond would be lost?

What I also don't understand (seems like I'm a bit dumb ) is why they would have to resign if they want to be together, when Ruth said 'what would we talk about with the neighbours' I got the sense it implied that, if they would become 'lovers' there would be no place for MI5 anymore in their lives, why is that? It's not that the service would reject them if they would marry, Adam and Fiona were married too and they still could do their job.
Or maybe that is the reason Ruth rejected Harry's proposal, because she thinks that if they come together, they wouldn't be able to do their saving-England-work anymore?